Layer of material for a surgical end effector

ABSTRACT

In various embodiments, a layer of material can comprise a body, a proximal end portion, and a distal end portion. The proximal end portion can be releasably secured to a staple cartridge of a surgical end effector, and the distal end portion can be releasably secured to an anvil of the surgical end effector. The layer of material can comprise a tissue thickness compensator.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application claiming priority under35 U.S.C. § 120 to U.S. patent application Ser. No. 13/766,325, entitledLAYER OF MATERIAL FOR A SURGICAL END EFFECTOR, filed Feb. 13, 2013, nowU.S. Patent Application Publication No. 2013/0256380, which is acontinuation application claiming priority under 35 U.S.C. § 120 to U.S.patent application Ser. No. 13/433,129, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING A PLURALITY OF MEDICAMENTS, filed on Mar. 28,2012, which issued on Dec. 15, 2015 as U.S. Pat. No. 9,211,120, theentire disclosures of which are hereby incorporated by reference herein.

BACKGROUND

The present invention relates to surgical instruments and, in variousembodiments, to surgical cutting and stapling instruments and staplecartridges therefor that are designed to cut and staple tissue.

BRIEF DESCRIPTION OF THE DRAWINGS

The features and advantages of this invention, and the manner ofattaining them, will become more apparent and the invention itself willbe better understood by reference to the following description ofembodiments of the invention taken in conjunction with the accompanyingdrawings, wherein:

FIG. 1 is a cross-sectional view of a surgical instrument embodiment;

FIG. 1A is a perspective view of one embodiment of an implantable staplecartridge;

FIGS. 1B-1E illustrate portions of an end effector clamping and staplingtissue with an implantable staple cartridge;

FIG. 2 is a partial cross-sectional side view of another end effectorcoupled to a portion of a surgical instrument with the end effectorsupporting a surgical staple cartridge and with the anvil thereof in anopen position;

FIG. 3 is another partial cross-sectional side view of the end effectorof FIG. 2 in a closed position;

FIG. 4 is another partial cross-sectional side view of the end effectorof FIGS. 2 and 3 as the knife bar is starting to advance through the endeffector;

FIG. 5 is another partial cross-sectional side view of the end effectorof FIGS. 2-4 with the knife bar partially advanced therethrough;

FIGS. 6A-6D diagram the deformation of a surgical staple positionedwithin a collapsible staple cartridge body in accordance with at leastone embodiment;

FIG. 7A is a diagram illustrating a staple positioned in a crushablestaple cartridge body;

FIG. 7B is a diagram illustrating the crushable staple cartridge body ofFIG. 7A being crushed by an anvil;

FIG. 7C is a diagram illustrating the crushable staple cartridge body ofFIG. 7A being further crushed by the anvil;

FIG. 7D is a diagram illustrating the staple of FIG. 7A in a fullyformed configuration and the crushable staple cartridge of FIG. 7A in afully crushed condition;

FIG. 8 is a top view of a staple cartridge in accordance with at leastone embodiment comprising staples embedded in a collapsible staplecartridge body;

FIG. 9 is an elevational view of the staple cartridge of FIG. 8;

FIG. 10 is an exploded perspective view of an alternative embodiment ofa compressible staple cartridge comprising staples therein and a systemfor driving the staples against an anvil;

FIG. 10A is a partial cut-away view of an alternative embodiment of thestaple cartridge of FIG. 10;

FIG. 11 is a cross-sectional view of the staple cartridge of FIG. 10;

FIG. 12 is an elevational view of a sled configured to traverse thestaple cartridge of FIG. 10 and move the staples to toward the anvil;

FIG. 13 is a diagram of a staple driver which can be lifted toward theanvil by the sled of FIG. 12;

FIG. 14 is a perspective view of a staple cartridge comprising a rigidsupport portion and a compressible tissue thickness compensator for usewith a surgical stapling instrument in accordance with at least oneembodiment of the invention;

FIG. 15 is a partially exploded view of the staple cartridge of FIG. 14;

FIG. 16 is a fully exploded view of the staple cartridge of FIG. 14;

FIG. 17 is another exploded view of the staple cartridge of FIG. 14without a warp covering the tissue thickness compensator;

FIG. 18 is a perspective view of a cartridge body, or support portion,of the staple cartridge of FIG. 14;

FIG. 19 is a top perspective view of a sled movable within the staplecartridge of FIG. 14 to deploy staples from the staple cartridge;

FIG. 20 is a bottom perspective view of the sled of FIG. 19;

FIG. 21 is an elevational view of the sled of FIG. 19;

FIG. 22 is a top perspective view of a driver configured to support oneor more staples and to be lifted upwardly by the sled of FIG. 19 toeject the staples from the staple cartridge;

FIG. 23 is a bottom perspective view of the driver of FIG. 22;

FIG. 24 is a wrap configured to at least partially surround acompressible tissue thickness compensator of a staple cartridge;

FIG. 25 is a partial cut away view of a staple cartridge comprising arigid support portion and a compressible tissue thickness compensatorillustrated with staples being moved from an unfired position to a firedposition during a first sequence;

FIG. 26 is an elevational view of the staple cartridge of FIG. 25;

FIG. 27 is a detail elevational view of the staple cartridge of FIG. 25;

FIG. 28 is a cross-sectional end view of the staple cartridge of FIG.25;

FIG. 29 is a bottom view of the staple cartridge of FIG. 25;

FIG. 30 is a detail bottom view of the staple cartridge of FIG. 25;

FIG. 31 is a longitudinal cross-sectional view of an anvil in a closedposition and a staple cartridge comprising a rigid support portion and acompressible tissue thickness compensator illustrated with staples beingmoved from an unfired position to a fired position during a firstsequence;

FIG. 32 is another cross-sectional view of the anvil and the staplecartridge of FIG. 31 illustrating the anvil in an open position afterthe firing sequence has been completed;

FIG. 33 is a partial detail view of the staple cartridge of FIG. 31illustrating the staples in an unfired position;

FIG. 34 is a cross-sectional elevational view of a staple cartridgecomprising a rigid support portion and a compressible tissue thicknesscompensator illustrating the staples in an unfired position;

FIG. 35 is a detail view of the staple cartridge of FIG. 34;

FIG. 36 is an elevational view of an anvil in an open position and astaple cartridge comprising a rigid support portion and a compressibletissue thickness compensator illustrating the staples in an unfiredposition;

FIG. 37 is an elevational view of an anvil in a closed position and astaple cartridge comprising a rigid support portion and a compressibletissue thickness compensator illustrating the staples in an unfiredposition and tissue captured between the anvil and the tissue thicknesscompensator;

FIG. 38 is a detail view of the anvil and staple cartridge of FIG. 37;

FIG. 39 is an elevational view of an anvil in a closed position and astaple cartridge comprising a rigid support portion and a compressibletissue thickness compensator illustrating the staples in an unfiredposition illustrating thicker tissue positioned between the anvil andthe staple cartridge;

FIG. 40 is a detail view of the anvil and staple cartridge of FIG. 39;

FIG. 41 is an elevational view of the anvil and staple cartridge of FIG.39 illustrating tissue having different thicknesses positioned betweenthe anvil and the staple cartridge;

FIG. 42 is a detail view of the anvil and staple cartridge of FIG. 39 asillustrated in FIG. 41;

FIG. 43 is a diagram illustrating a tissue thickness compensator whichis compensating for different tissue thickness captured within differentstaples;

FIG. 44 is a diagram illustrating a tissue thickness compensatorapplying a compressive pressure to one or more vessels that have beentransected by a staple line;

FIG. 45 is a diagram illustrating a circumstance wherein one or morestaples have been improperly formed;

FIG. 46 is a diagram illustrating a tissue thickness compensator whichcould compensate for improperly formed staples;

FIG. 47 is a diagram illustrating a tissue thickness compensatorpositioned in a region of tissue in which multiple staples lines haveintersected;

FIG. 48 is a diagram illustrating tissue captured within a staple;

FIG. 49 is a diagram illustrating tissue and a tissue thicknesscompensator captured within a staple;

FIG. 50 is a diagram illustrating tissue captured within a staple;

FIG. 51 is a diagram illustrating thick tissue and a tissue thicknesscompensator captured within a staple;

FIG. 52 is a diagram illustrating thin tissue and a tissue thicknesscompensator captured within a staple;

FIG. 53 is a diagram illustrating tissue having an intermediatethickness and a tissue thickness compensator captured within a staple;

FIG. 54 is a diagram illustrating tissue having another intermediatethickness and a tissue thickness compensator captured within a staple;

FIG. 55 is a diagram illustrating thick tissue and a tissue thicknesscompensator captured within a staple;

FIG. 56 is a partial cross-sectional view of an end effector of asurgical stapling instrument illustrating a firing bar and staple-firingsled in a retracted, unfired position;

FIG. 57 is another partial cross-sectional view of the end effector ofFIG. 56 illustrating the firing bar and the staple-firing sled in apartially advanced position;

FIG. 58 is a cross-sectional view of the end effector of FIG. 56illustrating the firing bar in a fully advanced, or fired, position;

FIG. 59 is a cross-sectional view of the end effector of FIG. 56illustrating the firing bar in a retracted position after being firedand the staple-firing sled left in its fully fired position;

FIG. 60 is a detail view of the firing bar in the retracted position ofFIG. 59;

FIG. 61 is an exploded view of a retainer assembly including a retainerand two tissue thickness compensators in accordance with at least oneembodiment;

FIG. 62 is a perspective view of the retainer assembly shown in FIG. 61;

FIG. 63 is a perspective view of an anvil with which the retainerassembly of FIG. 61 may be used;

FIG. 64 is an illustration depicting the retainer assembly shown in FIG.61 being inserted in an end effector of a surgical stapler whichincludes an anvil and a staple cartridge;

FIG. 65 is a side view of the retainer assembly shown in FIG. 61 engagedwith the staple cartridge of FIG. 64;

FIG. 66 is a side view of the retainer assembly shown in FIG. 61 engagedwith the staple cartridge and the anvil of FIG. 64 illustrating theanvil in a closed position;

FIG. 67 is a side view of the retainer assembly of FIG. 61 being removedfrom the end effector of FIG. 64;

FIG. 68 is a perspective view of a retainer;

FIG. 69 is a side view of the retainer of FIG. 68 with tissue thicknesscompensators attached to bottom and top surfaces thereof illustratingone of the tissue thickness compensators engaged with a staple cartridgein a surgical stapler comprising an anvil;

FIG. 70 is a side view illustrating the anvil of FIG. 69 in a closedposition;

FIG. 71 is an exploded perspective view of a retainer and a tissuethickness compensator in accordance with at least one embodiment;

FIG. 72 is an exploded perspective view of the tissue thicknesscompensator of FIG. 71 and an anvil of a surgical stapler;

FIG. 73 is an exploded top perspective view of a retainer and a tissuethickness compensator in accordance with at least one embodiment;

FIG. 74 is an exploded bottom perspective view of the retainer andtissue thickness compensator of FIG. 73;

FIG. 75 is a top perspective view of the retainer and tissue thicknesscompensator of FIG. 73 engaged with a surgical stapler;

FIG. 76 is a bottom perspective view of the retainer and tissuethickness compensator of FIG. 73 engaged with the surgical stapler ofFIG. 75;

FIG. 77 is a side view of the retainer and tissue thickness compensatorof FIG. 73 engaged with the surgical stapler of FIG. 75;

FIG. 78 is a bottom perspective view of the retainer and tissuethickness compensator of FIG. 73 illustrating the tissue thicknesscompensator attached to the anvil of the surgical stapler of FIG. 75;

FIG. 79 is a top perspective view of the retainer and tissue thicknesscompensator of FIG. 73 illustrating the tissue thickness compensatorattached to the anvil of FIG. 78;

FIG. 80 is a side view of the tissue thickness compensator of FIG. 73attached to the anvil of FIG. 78;

FIG. 81 is a cross-sectional view of the retainer and tissue thicknesscompensator of FIGS. 73 and 74 attached to a staple cartridge andchannel of a surgical stapler;

FIG. 82 is a cross-sectional view of the retainer and tissue thicknesscompensator of FIGS. 73 and 74 attached to the staple cartridge andchannel of the surgical stapler of FIG. 81 illustrating an anvil of thesurgical stapler engaged with the tissue thickness compensator;

FIG. 83 is a cross-sectional view of the tissue thickness compensator ofFIG. 73 attached to the anvil of the surgical stapler and being movedaway from the retainer;

FIG. 84 is a side cross-sectional view of a retainer assembly comprisinga retainer, tissue thickness compensators mounted on first and secondsurfaces of the retainer, and connectors passing through holes in theretainer in accordance with at least one embodiment;

FIG. 85 is a perspective view of the retainer assembly of FIG. 84illustrated with a portion of a tissue thickness compensator removed forthe purposes of illustration;

FIG. 86 is a side view of the retainer assembly of FIG. 84 engaged witha surgical stapler comprising an anvil illustrated in an open position;

FIG. 87 is a side view of the retainer assembly of FIG. 84 and the anvilof FIG. 86 illustrated in a closed position;

FIG. 88 is a side view of the retainer assembly of FIG. 84 illustratingthe retainer being removed from between the tissue thicknesscompensators of the retainer assembly;

FIG. 89 is a side view of the retainer removed from the tissue thicknesscompensators of FIG. 84;

FIG. 90 is a perspective view of a retainer configured to engage ananvil of a surgical stapler in accordance with at least one embodiment;

FIG. 91 is a top view of the retainer of FIG. 90;

FIG. 92 is a side view of the retainer of FIG. 90;

FIG. 93 is a bottom view of the retainer of FIG. 90;

FIG. 94 illustrates a retainer assembly comprising the retainer of FIG.90 and a tissue thickness compensator being attached to a staplecartridge for a surgical stapler;

FIG. 95 illustrates the retainer assembly and staple cartridge of FIG.94 engaging an anvil of an end effector of a surgical stapler;

FIG. 96 illustrates the retainer assembly and staple cartridge of FIG.94 engaging the anvil of the end effector of the surgical stapler ofFIG. 95;

FIG. 97 illustrates the retainer assembly and staple cartridge of FIG.94 engaged on the anvil of the surgical stapler of FIG. 95;

FIG. 98 illustrates the retainer assembly and staple cartridge of FIG.94 engaged on the anvil of the surgical stapler of FIG. 95 and the anvilbeing moved into a closed position;

FIG. 99 illustrates the anvil of the surgical stapler of FIG. 95 in anopen position with the tissue thickness compensator attached thereto andthe retainer engaged with the staple cartridge channel of the surgicalstapler;

FIG. 100 illustrates the retainer of FIG. 94 engaged with the staplecartridge channel of the surgical stapler of FIG. 95 and the anvil in anopen position;

FIG. 101 is a cross-sectional view of a retainer including a tissuethickness compensator comprising protrusions or wings configured toengage an anvil of a surgical stapler;

FIG. 102 is a cross-sectional view of a retainer including a tissuethickness compensator comprising a sock configured to engage an anvil ofa surgical stapler;

FIG. 103 is a perspective view of a retainer that includes two platesconnected by a hinge according to at least one embodiment;

FIG. 104 is a side view of the retainer of FIG. 103;

FIG. 105 is a rear perspective view of an embodiment of an insertiontool configured for use with the retainer of FIG. 103;

FIG. 106 is a top perspective view of the insertion tool of FIG. 105;

FIG. 107 is a rear perspective view of the insertion tool of FIG. 105with a portion of the insertion tool removed for purposes ofillustration;

FIG. 108 is a side view of the insertion tool of FIG. 105 with a portionof the insertion tool removed for purposes of illustration;

FIG. 109 is a top view of the insertion tool of FIG. 105;

FIG. 110 is a perspective view of a retainer assembly comprising theretainer of FIG. 103, a tissue thickness compensator positioned on theretainer, a staple cartridge positioned on the retainer, and theinsertion tool of FIG. 105 engaged with the retainer, wherein a portionof the insertion tool is removed for purposes of illustration;

FIG. 111 is a side view of a retainer assembly comprising the retainerof FIG. 103, a tissue thickness compensator positioned on the retainer,and the insertion tool of FIG. 105 engaged with the retainer, wherein aportion of the insertion tool is removed for purposes of illustration;

FIG. 112 illustrates the retainer assembly of FIG. 110 being insertedinto a surgical instrument comprising an anvil and a staple cartridgechannel, wherein a portion of the insertion tool is removed for thepurposes of illustration;

FIG. 113 illustrates the retainer assembly of FIG. 110 being insertedinto a surgical instrument comprising an anvil and a staple cartridgechannel, wherein a portion of the insertion tool is removed for thepurposes of illustration;

FIG. 114 illustrates the insertion tool of FIG. 105 being moved relativeto the retainer to engage the staple cartridge in the staple cartridgechannel and to engage the tissue thickness compensator with the anvil,wherein a portion of the insertion tool is removed for the purposes ofillustration;

FIG. 115 illustrates the insertion tool of FIG. 105 being moved relativeto the retainer to disengage the retainer from the tissue thicknesscompensator and from the staple cartridge, wherein a portion of theinsertion tool is removed for the purposes of illustration;

FIG. 116 is a cross-sectional view of a tissue thickness compensatorattached to an anvil of a surgical stapling instrument in accordancewith at least one embodiment;

FIG. 117 is a diagram illustrating deformed staples at least partiallycapturing the tissue thickness compensator of FIG. 116 therein;

FIG. 118 is a cross-sectional view of an end effector of a surgicalstapling instrument including a staple cartridge comprising a firsttissue thickness compensator and an anvil comprising a second tissuethickness compensator in accordance with at least one embodiment;

FIG. 119 is a cross-sectional view of the end effector of FIG. 118illustrating staples from the staple cartridge moved from an unfiredposition to a fired position;

FIG. 120 is a perspective view of a tissue thickness compensatorattached to an anvil of an end effector wherein the tissue thicknesscompensator comprises a plurality of capsules in accordance with atleast one embodiment;

FIG. 120A is a partial perspective view of the tissue thicknesscompensator of FIG. 120;

FIG. 121 is a cross-sectional view of staples being moved from anunfired position to a fired position to puncture the capsules of thetissue thickness compensator of FIG. 120;

FIG. 122 is an exploded view of an anvil and a tissue thicknesscompensator in accordance with at least one embodiment;

FIG. 123 is a cross-sectional view of an anvil comprising a plurality ofstaple forming pockets and a tissue thickness compensator comprising aplurality of capsules aligned with the forming pockets in accordancewith at least one embodiment;

FIG. 124 is a detail view of the capsules of the tissue thicknesscompensator of FIG. 123;

FIG. 125 is a diagram illustrating the anvil and the tissue thicknesscompensator of FIG. 123 positioned relative to tissue which is to bestapled by staples from a staple cartridge positioned on the oppositeside of the tissue;

FIG. 126 is a diagram illustrating the anvil of FIG. 123 moved towardthe staple cartridge of FIG. 125 and staples partially fired from thestaple cartridge;

FIG. 127 is a diagram illustrating the staples of FIG. 126 in afully-fired configuration and the capsules of the tissue thicknesscompensator of FIG. 123 in a ruptured state;

FIG. 128 is a diagram illustrating a staple of FIG. 126 in a misfiredcondition;

FIG. 129 is a diagram illustrating the staples of FIG. 126 in afully-fired configuration and the tissue thickness compensator of FIG.123 in at least partially transected condition;

FIG. 130 is a cross-sectional perspective view of an alternativeembodiment of a tissue thickness compensator in accordance with at leastone embodiment;

FIG. 131 is a perspective view of an alternative embodiment of a tissuethickness compensator comprising a plurality of capsules aligned with acutting member of a surgical stapling instrument;

FIG. 132 is a detail view of the capsules of FIG. 131;

FIG. 133 is a cross-sectional view of the tissue thickness compensatorof FIG. 131 comprising a plurality of capsules aligned with a knife slotof an anvil of a surgical stapling instrument;

FIGS. 134 and 135 illustrate an alternative embodiment of a tissuethickness compensator being attached to an anvil;

FIG. 136 is a cross-sectional exploded view of an anvil and acompensator in accordance with at least one embodiment;

FIG. 137 illustrates the compensator of FIG. 136 attached to the anvil;

FIG. 138 is a partial perspective view of a tissue thickness compensatorand a cutting member incising the tissue thickness compensator inaccordance with at least one embodiment;

FIG. 139 is a partial cross-sectional view of an alternative embodimentof a tissue thickness compensator in accordance with at least oneembodiment;

FIG. 140 is a partial cross-sectional view of another alternativeembodiment of a tissue thickness compensator in accordance with at leastone embodiment;

FIG. 141 is an illustration depicting a tissue thickness compensatorcomprising a plurality of irregular and/or asymmetrical cavities inaccordance with various embodiments;

FIG. 142 is a partial cut-away view of a tissue thickness compensatorattached to an anvil of a surgical stapling instrument in accordancewith at least one embodiment;

FIG. 143 is a perspective view of a seamless extruded casing, or outertube, of a tissue thickness compensator in accordance with at least oneembodiment;

FIG. 144 is a perspective view of another seamless extruded casing, orouter tube, of a tissue thickness compensator in accordance with atleast one embodiment;

FIG. 145 is a perspective view of oxidized regenerated cellulose fibers;

FIG. 146 is a perspective view of oxidized regenerated cellulose fiberswhich are shorter than the fibers of FIG. 145;

FIG. 147 is a diagram illustrating the fibers of FIG. 145 being woveninto a strand utilizing the fibers of FIG. 146;

FIG. 148 depicts the strand of FIG. 147 being fluffed and at leastpartially cut;

FIG. 149 depicts a grasper inserted through a casing, or outer tube, ofa tissue thickness compensator and positioned to grasp the strand ofFIG. 147;

FIG. 150 illustrates the grasper of FIG. 149 being withdrawn from thecasing and the strand of FIG. 147 being pulled through the casing;

FIG. 151 illustrates the casing and the strand of FIG. 150 beingsegmented;

FIG. 152 illustrates the ends of the casing being heat-welded and/orsealed;

FIG. 153 illustrates a process for creating a tissue thicknesscompensator without lateral seams;

FIG. 154 illustrates an anvil of a surgical stapling instrument and aplurality of compensators which can be selectively attached to theanvil, wherein each of the compensators comprises an array of capillarychannels;

FIG. 155 is a plan view of a compensator configured to be attached to ananvil;

FIG. 156 is a detail view of a portion of the compensator of FIG. 155;

FIG. 157 is a perspective view of an end effector of a surgical staplinginstrument;

FIG. 158 is another perspective view of the end effector of FIG. 157illustrating a fluid being placed on a tissue thickness compensator ofthe end effector;

FIG. 159 is another perspective view of the end effector of FIG. 159illustrating a compensator attached to an anvil of the end effector;

FIG. 160 is a detail view of an array of capillary channels on thecompensator of FIG. 159;

FIG. 161 is an exploded view of a compensator comprising a plurality oflayers in accordance with at least one embodiment;

FIG. 162 is an exploded view of a compensator and an anvil of a surgicalstapling instrument in accordance with at least one embodiment;

FIG. 163 is a partial cross-sectional view of the compensator and theanvil of FIG. 162;

FIG. 164 is an exploded view of a compensator comprising a cellularingrowth matrix in accordance with at least one embodiment;

FIG. 165 is a perspective view of the compensator of FIG. 164;

FIG. 166 is a perspective view of a fibrous layer of material for acompensator;

FIG. 167 is a perspective view of a plurality of fibrous layers stackedon one another in accordance with at least one embodiment;

FIG. 168 is a perspective view of another plurality of fibrous layersstacked on one another in accordance with at least one embodiment;

FIG. 169 is a perspective view of a fibrous layer of material for acompensator;

FIG. 170 is a perspective view of a plurality of fibrous layers stackedon one another wherein the fibers are arranged in different directionsin accordance with at least one embodiment;

FIG. 171 is a perspective view of another plurality of fibrous layersstacked on one another in accordance with at least one embodiment;

FIG. 172 is a perspective view of an end effector insert and an endeffector of a surgical instrument in accordance with at least oneembodiment;

FIG. 173 is an elevational view of a tissue thickness compensatorpositioned in an end effector of a surgical instrument in accordancewith at least one embodiment;

FIG. 174 is an elevational view of a tissue thickness compensatorpositioned in the end effector of the surgical instrument in accordancewith at least one embodiment;

FIG. 175 is a perspective view of a sleeve positioned on an anvil forthe end effector of the surgical instrument in accordance with at leastone embodiment;

FIG. 176 is a plan view of a pronged portion of the sleeve of FIG. 175;

FIG. 177 is an elevational view of the pronged portion of the sleeve ofFIG. 175;

FIG. 178 is an end view of the pronged portion of the sleeve of FIG.175;

FIG. 179 is a perspective view of the pronged portion of the sleeve ofFIG. 175;

FIG. 180 is a plan view of a tissue compensator of a sleeve inaccordance with at least one embodiment;

FIG. 181 is a perspective view of the tissue compensator of FIG. 180;

FIG. 182 is an elevational view of the tissue compensator of FIG. 180;

FIG. 183 is a plan view of a tissue compensator of a sleeve inaccordance with at least one embodiment;

FIG. 184 is a perspective view of the tissue compensator of FIG. 183;

FIG. 185 is an elevational view of the tissue compensator of FIG. 183;

FIG. 186 is a perspective view of a nose of the sleeve of FIG. 175;

FIG. 187 is another perspective view of the nose of FIG. 186;

FIG. 188 is a plan view of the nose of FIG. 186 depicting the innergeometry in phantom lines;

FIG. 189 is an elevational view of the nose of FIG. 186 depicting theinner geometry in phantom lines;

FIG. 190 is another perspective view of the sleeve of FIG. 175positioned on the anvil;

FIG. 191 is a plan view of the sleeve of FIG. 175 positioned on theanvil;

FIG. 192 is an elevational view of the sleeve of FIG. 175 positioned onthe anvil;

FIG. 193 is a plan view of the sleeve of FIG. 175 positioned on theanvil depicting a translating firing bar shown in phantom lines;

FIG. 194 is an elevational view of the sleeve of FIG. 175 positioned onthe anvil depicting a translating firing bar shown in phantom lines;

FIG. 195 is a plan view of the sleeve of FIG. 175 positioned on theanvil depicting the release of the nose from the sleeve;

FIG. 196 is an elevational view of the sleeve of FIG. 175 positioned onthe anvil depicting the release of the nose from the sleeve;

FIG. 197 is a plan view of the sleeve of FIG. 175 positioned on theanvil depicting the firing bar in phantom lines and the release of thenose from the sleeve;

FIG. 198 is an elevational view of the sleeve of FIG. 175 positioned onthe anvil depicting the firing bar in phantom lines and the release ofthe nose from the sleeve;

FIG. 199 is a partial perspective view of the sleeve, the anvil, and thefiring bar of FIG. 197;

FIG. 200 is another partial perspective view of the sleeve, the anvil,and the firing bar of FIG. 197;

FIG. 201 is an elevational cross-sectional view of the sleeve and theanvil of FIG. 175;

FIG. 202 is an elevational cross-sectional view of the anvil of FIG. 175depicting the release of the tissue compensator from the sleeve;

FIG. 203 is a plan view of an end effector insert in accordance with atleast one embodiment;

FIG. 204 is an elevational view of the end effector insert of FIG. 203;

FIG. 205 is a perspective view of the end effector insert of FIG. 205;

FIG. 206 is a partial perspective view of the end effector insert ofFIG. 203 depicting the end effector insert engaging the anvil of the endeffector of a surgical instrument;

FIG. 207 is a partial perspective view of the end effector insert ofFIG. 203 depicting the end effector insert engaging the staple cartridgeof the end effector of a surgical instrument;

FIG. 208 is an elevational view of the end effector insert of FIG. 203depicting the end effector insert engaging the end effector of asurgical instrument;

FIG. 209 is an elevational view of the end effector insert of FIG. 203positioned in the end effector of a surgical instrument;

FIG. 210 is a perspective view of a tissue thickness compensatorpositioned in the end effector of a surgical instrument in accordancewith at least one embodiment illustrated with a portion of the tissuethickness compensator cut away;

FIG. 211 is a perspective view of the tissue thickness compensator ofFIG. 210 secured to the anvil of the end effector by a static charge;

FIG. 212 is a perspective view of the tissue thickness compensator ofFIG. 210 secured to the anvil of the end effector by suction elements;

FIG. 213 is a perspective view of the tissue thickness compensator ofFIG. 210 secured to the anvil of the end effector by hook and loopfasteners;

FIG. 214 is a partial perspective view of the tissue thicknesscompensator of FIG. 210 secured to the anvil of the end effector by aband;

FIG. 215 is a partial perspective view of the tissue thicknesscompensator of FIG. 210 secured to the anvil of the end effector by asock at the distal end of the tissue thickness compensator;

FIG. 216 is a perspective partial cross-sectional view of a tissuethickness compensator secured to the anvil of the end effector of asurgical instrument in accordance with at least one embodiment;

FIG. 217 is an elevational cross-sectional view of the tissue thicknesscompensator of FIG. 216;

FIG. 218 is another elevational cross-sectional view of the tissuethickness compensator of FIG. 216;

FIG. 219 is an elevational cross-sectional view of a tissue thicknesscompensator secured to the anvil of the end effector of a surgicalinstrument depicting a latch in a closed position in accordance with atleast one embodiment;

FIG. 220 is an elevational cross-sectional view the tissue thicknesscompensator of FIG. 219 depicting the latch in the open position;

FIG. 221 is an elevational cross-sectional view of a tissue thicknesscompensator secured to the anvil of the end effector of a surgicalinstrument in accordance with at least one embodiment;

FIG. 222 is an elevational cross-sectional view of a tissue thicknesscompensator secured to the anvil of the end effector of a surgicalinstrument in accordance with at least one embodiment;

FIG. 223 is an elevational cross-sectional view of a tissue thicknesscompensator secured to the anvil of the end effector of a surgicalinstrument in accordance with at least one embodiment;

FIG. 224 is an elevational cross-sectional view of a tissue thicknesscompensator secured to the anvil of the end effector of the surgicalinstrument in accordance with at least one embodiment;

FIG. 225 is a perspective cross-sectional exploded view of a tissuethickness compensator secured to an anvil of an end effector of thesurgical instrument in accordance with at least one embodiment;

FIG. 226 is a perspective view of the tissue thickness compensator ofFIG. 225 depicting movement of the tissue thickness compensator towardsthe anvil;

FIG. 227 is an elevational cross-sectional view of the tissue thicknesscompensator of FIG. 225 engaged with the anvil;

FIG. 228 is a perspective cross-sectional view of a tissue thicknesscompensator secured to the anvil of the end effector of a surgicalinstrument in accordance with at least one embodiment;

FIG. 229 is a perspective cross-sectional exploded view of the tissuethickness compensator and the anvil of FIG. 228;

FIG. 230 is an elevational view of a tissue thickness compensator inaccordance with at least one embodiment;

FIG. 231 is a perspective view of the tissue thickness compensator ofFIG. 230;

FIG. 232 is another perspective of the tissue thickness compensator ofFIG. 230;

FIG. 233 is a perspective view of the tissue thickness compensator ofFIG. 230 depicting movement of the tissue thickness compensator towardsthe anvil of the end effector of a surgical instrument;

FIG. 234 is a plan cross-sectional view of the tissue thicknesscompensator of FIG. 230 positioned on the anvil;

FIG. 235 is a perspective view of the tissue thickness compensator ofFIG. 230 positioned on the anvil;

FIG. 236 is a perspective view of the tissue thickness compensator ofFIG. 230 positioned on the anvil illustrating a cutting element severingthe tissue thickness compensator;

FIG. 237 is a cross-sectional elevational view of an end effector of asurgical stapling instrument comprising an anvil and a chargeable layerin accordance with at least one embodiment;

FIG. 238 is a bottom view of the anvil and the chargeable layer of FIG.237;

FIG. 239 is an exploded view of the anvil and the chargeable layer ofFIG. 237 and a tissue thickness compensator releasably attachable to thechargeable layer;

FIG. 240 is a perspective view of a tissue thickness compensator inaccordance with at least one embodiment;

FIG. 241 is a plan view of the tissue thickness compensator of FIG. 240;

FIG. 240A is a perspective view of a tissue thickness compensator inaccordance with at least one alternative embodiment;

FIG. 241A is a plan view of the tissue thickness compensator of FIG.240A;

FIG. 242 is a perspective view of a tissue thickness compensator inaccordance with at least one alternative embodiment;

FIG. 243 is a plan view of the tissue thickness compensator of FIG. 242;

FIG. 244 is a perspective view of a tissue thickness compensator inaccordance with at least one embodiment;

FIG. 245 is a perspective view of a tissue thickness compensatorattached to an anvil in accordance with at least one embodiment;

FIG. 246 is a cross-sectional view of the anvil and the tissue thicknesscompensator of FIG. 245;

FIG. 247 is a cross-sectional view of the tissue thickness compensatorof FIG. 245;

FIG. 248 is a perspective view of a tissue thickness compensatorattached to an anvil in accordance with at least one alternativeembodiment;

FIG. 249 is a cross-sectional view of the anvil and the tissue thicknesscompensator of FIG. 248;

FIG. 250 is a cross-sectional view of the tissue thickness compensatorof FIG. 248 in an open configuration;

FIG. 251 is a perspective view of a tissue thickness compensatorattached to an anvil in accordance with at least one alternativeembodiment;

FIG. 252 is a cross-sectional view of the anvil and the tissue thicknesscompensator of FIG. 251;

FIG. 253 is a perspective view of a tissue thickness compensatorattached to an anvil in accordance with at least one alternativeembodiment;

FIG. 254 is a cross-sectional view of the anvil and the tissue thicknesscompensator of FIG. 253;

FIG. 255 is a perspective view of a tissue thickness compensatorattached to an anvil in accordance with at least one alternativeembodiment;

FIG. 256 is a cross-sectional view of the anvil and the tissue thicknesscompensator of FIG. 255;

FIG. 257 is a perspective view of a tissue thickness compensatorattached to an anvil in accordance with at least one alternativeembodiment; and

FIG. 258 is a cross-sectional view of the anvil and the tissue thicknesscompensator of FIG. 257.

Corresponding reference characters indicate corresponding partsthroughout the several views. The exemplifications set out hereinillustrate certain embodiments of the invention, in one form, and suchexemplifications are not to be construed as limiting the scope of theinvention in any manner.

DETAILED DESCRIPTION

The Applicant of the present application also owns the U.S. PatentApplications identified below which are each herein incorporated byreference in their respective entirety:

U.S. patent application Ser. No. 12/894,311, entitled SURGICALINSTRUMENTS WITH RECONFIGURABLE SHAFT SEGMENTS, now U.S. Pat. No.8,763,877;

U.S. patent application Ser. No. 12/894,340, entitled SURGICAL STAPLECARTRIDGES SUPPORTING NON-LINEARLY ARRANGED STAPLES AND SURGICALSTAPLING INSTRUMENTS WITH COMMON STAPLE-FORMING POCKETS, now U.S. Pat.No. 8,899,463;

U.S. patent application Ser. No. 12/894,327, entitled JAW CLOSUREARRANGEMENTS FOR SURGICAL INSTRUMENTS, now U.S. Pat. No. 8,978,956;

U.S. patent application Ser. No. 12/894,351, entitled SURGICAL CUTTINGAND FASTENING INSTRUMENTS WITH SEPARATE AND DISTINCT FASTENER DEPLOYMENTAND TISSUE CUTTING SYSTEMS, now U.S. Pat. No. 9,113,864;

U.S. patent application Ser. No. 12/894,338, entitled IMPLANTABLEFASTENER CARTRIDGE HAVING A NON-UNIFORM ARRANGEMENT, now U.S. Pat. No.8,864,007;

U.S. patent application Ser. No. 12/894,369, entitled IMPLANTABLEFASTENER CARTRIDGE COMPRISING A SUPPORT RETAINER, now U.S. PatentApplication Publication No. 2012/0080344;

U.S. patent application Ser. No. 12/894,312, entitled IMPLANTABLEFASTENER CARTRIDGE COMPRISING MULTIPLE LAYERS, now U.S. Pat. No.8,925,782;

U.S. patent application Ser. No. 12/894,377, entitled SELECTIVELYORIENTABLE IMPLANTABLE FASTENER CARTRIDGE, now U.S. Pat. No. 8,393,514;

U.S. patent application Ser. No. 12/894,339, entitled SURGICAL STAPLINGINSTRUMENT WITH COMPACT ARTICULATION CONTROL ARRANGEMENT, now U.S. Pat.No. 8,840,003;

U.S. patent application Ser. No. 12/894,360, entitled SURGICAL STAPLINGINSTRUMENT WITH A VARIABLE STAPLE FORMING SYSTEM, now U.S. Pat. No.9,113,862;

U.S. patent application Ser. No. 12/894,322, entitled SURGICAL STAPLINGINSTRUMENT WITH INTERCHANGEABLE STAPLE CARTRIDGE ARRANGEMENTS, now U.S.Pat. No. 8,740,034;

U.S. patent application Ser. No. 12/894,350, entitled SURGICAL STAPLECARTRIDGES WITH DETACHABLE SUPPORT STRUCTURES AND SURGICAL STAPLINGINSTRUMENTS WITH SYSTEMS FOR PREVENTING ACTUATION MOTIONS WHEN ACARTRIDGE IS NOT PRESENT, now U.S. Patent Application Publication No.2012/0080478;

U.S. patent application Ser. No. 12/894,383, entitled IMPLANTABLEFASTENER CARTRIDGE COMPRISING BIOABSORBABLE LAYERS, now U.S. Pat. No.8,752,699;

U.S. patent application Ser. No. 12/894,389, entitled COMPRESSIBLEFASTENER CARTRIDGE, now U.S. Pat. No. 8,740,037;

U.S. patent application Ser. No. 12/894,345, entitled FASTENERSSUPPORTED BY A FASTENER CARTRIDGE SUPPORT, now U.S. Pat. No. 8,783,542;

U.S. patent application Ser. No. 12/894,306, entitled COLLAPSIBLEFASTENER CARTRIDGE, now U.S. Pat. No. 9,044,227;

U.S. patent application Ser. No. 12/894,318, entitled FASTENER SYSTEMCOMPRISING A PLURALITY OF CONNECTED RETENTION MATRIX ELEMENTS, now U.S.Pat. No. 8,814,024;

U.S. patent application Ser. No. 12/894,330, entitled FASTENER SYSTEMCOMPRISING A RETENTION MATRIX AND AN ALIGNMENT MATRIX, now U.S. Pat. No.8,757,465;

U.S. patent application Ser. No. 12/894,361, entitled FASTENER SYSTEMCOMPRISING A RETENTION MATRIX, now U.S. Pat. No. 8,529,600;

U.S. patent application Ser. No. 12/894,367, entitled FASTENINGINSTRUMENT FOR DEPLOYING A FASTENER SYSTEM COMPRISING A RETENTIONMATRIX, now U.S. Pat. No. 9,033,203;

U.S. patent application Ser. No. 12/894,388, entitled FASTENER SYSTEMCOMPRISING A RETENTION MATRIX AND A COVER, now U.S. Pat. No. 8,474,677;

U.S. patent application Ser. No. 12/894,376, entitled FASTENER SYSTEMCOMPRISING A PLURALITY OF FASTENER CARTRIDGES, now U.S. Pat. No.9,044,228;

U.S. patent application Ser. No. 13/097,865, entitled SURGICAL STAPLERANVIL COMPRISING A PLURALITY OF FORMING POCKETS, now U.S. Pat. No.9,295,464;

U.S. patent application Ser. No. 13/097,936, entitled TISSUE THICKNESSCOMPENSATOR FOR A SURGICAL STAPLER, now U.S. Pat. No. 8,657,176;

U.S. patent application Ser. No. 13/097,954, entitled STAPLE CARTRIDGECOMPRISING A VARIABLE THICKNESS COMPRESSIBLE PORTION, now U.S. PatentApplication Publication No. 2012/0080340;

U.S. patent application Ser. No. 13/097,856, entitled STAPLE CARTRIDGECOMPRISING STAPLES POSITIONED WITHIN A COMPRESSIBLE PORTION THEREOF, nowU.S. Patent Application Publication No. 2012/0080336;

U.S. patent application Ser. No. 13/097,928, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING DETACHABLE PORTIONS, now U.S. Pat. No. 8,746,535;

U.S. patent application Ser. No. 13/097,891, entitled TISSUE THICKNESSCOMPENSATOR FOR A SURGICAL STAPLER COMPRISING AN ADJUSTABLE ANVIL, nowU.S. Pat. No. 8,864,009;

U.S. patent application Ser. No. 13/097,948, entitled STAPLE CARTRIDGECOMPRISING AN ADJUSTABLE DISTAL PORTION, now U.S. Pat. No. 8,978,954;

U.S. patent application Ser. No. 13/097,907, entitled COMPRESSIBLESTAPLE CARTRIDGE ASSEMBLY, now U.S. Pat. No. 9,301,755;

U.S. patent application Ser. No. 13/097,861, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING PORTIONS HAVING DIFFERENT PROPERTIES, now U.S.Pat. No. 9,113,865;

U.S. patent application Ser. No. 13/097,869, entitled STAPLE CARTRIDGELOADING ASSEMBLY, now U.S. Pat. No. 8,857,694;

U.S. patent application Ser. No. 13/097,917, entitled COMPRESSIBLESTAPLE CARTRIDGE COMPRISING ALIGNMENT MEMBERS, now U.S. Pat. No.8,777,004;

U.S. patent application Ser. No. 13/097,873, entitled STAPLE CARTRIDGECOMPRISING A RELEASABLE PORTION, now U.S. Pat. No. 8,740,038;

U.S. patent application Ser. No. 13/097,938, entitled STAPLE CARTRIDGECOMPRISING COMPRESSIBLE DISTORTION RESISTANT COMPONENTS, now U.S. Pat.No. 9,016,542;

U.S. patent application Ser. No. 13/097,924, entitled STAPLE CARTRIDGECOMPRISING A TISSUE THICKNESS COMPENSATOR, now U.S. Pat. No. 9,168,038;

U.S. patent application Ser. No. 13/242,029, entitled SURGICAL STAPLERWITH FLOATING ANVIL, now U.S. Pat. No. 8,893,949;

U.S. patent application Ser. No. 13/242,066, entitled CURVED ENDEFFECTOR FOR A STAPLING INSTRUMENT, now U.S. Patent ApplicationPublication No. 2012/0080498;

U.S. patent application Ser. No. 13/242,086, entitled STAPLE CARTRIDGEINCLUDING COLLAPSIBLE DECK, now U.S. Pat. No. 9,055,941;

U.S. patent application Ser. No. 13/241,912, entitled STAPLE CARTRIDGEINCLUDING COLLAPSIBLE DECK ARRANGEMENT, now U.S. Pat. No. 9,050,084;

U.S. patent application Ser. No. 13/241,922, entitled SURGICAL STAPLERWITH STATIONARY STAPLE DRIVERS, now U.S. Pat. No. 9,216,019;

U.S. patent application Ser. No. 13/241,637, entitled SURGICALINSTRUMENT WITH TRIGGER ASSEMBLY FOR GENERATING MULTIPLE ACTUATIONMOTIONS, now U.S. Pat. No. 8,789,741; and

U.S. patent application Ser. No. 13/241,629, entitled SURGICALINSTRUMENT WITH SELECTIVELY ARTICULATABLE END EFFECTOR, now U.S. PatentApplication Publication No. 2012/0074200.

The Applicant of the present application also owns the U.S. PatentApplications identified below which were filed on Mar. 28, 2012 andwhich are each herein incorporated by reference in their respectiveentirety:

U.S. patent application Ser. No. 13/433,096, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING A PLURALITY OF CAPSULES, now U.S. Pat. No.9,301,752;

U.S. patent application Ser. No. 13/433,103, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING A PLURALITY OF LAYERS, now U.S. Pat. No.9,433,419;

U.S. patent application Ser. No. 13/433,098 entitled EXPANDABLE TISSUETHICKNESS COMPENSATOR, now U.S. Pat. No. 9,301,753;

U.S. patent application Ser. No. 13/433,102, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING A RESERVOIR, now U.S. Pat. No. 9,232,941;

U.S. patent application Ser. No. 13/433,114, entitled RETAINER ASSEMBLYINCLUDING A TISSUE THICKNESS COMPENSATOR, now U.S. Pat. No. 9,386,988;

U.S. patent application Ser. No. 13/433,136, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING AT LEAST ONE MEDICAMENT, now U.S. PatentApplication Publication No. 2012/0241492;

U.S. patent application Ser. No. 13/433,141, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING CONTROLLED RELEASE AND EXPANSION, now U.S. PatentApplication Publication No. 2012/0241493;

U.S. patent application Ser. No. 13/433,144, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING FIBERS TO PRODUCE A RESILIENT LOAD, now U.S. Pat.No. 9,277,919;

U.S. patent application Ser. No. 13/433,148, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING STRUCTURE TO PRODUCE A RESILIENT LOAD, now U.S.Pat. No. 9,220,500;

U.S. patent application Ser. No. 13/433,155, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING RESILIENT MEMBERS, now U.S. Pat. No. 9,480,476;

U.S. patent application Ser. No. 13/433,163, entitled METHODS FORFORMING TISSUE THICKNESS COMPENSATOR ARRANGEMENTS FOR SURGICAL STAPLERS,now U.S. Patent Application Publication No. 2012/0248169;

U.S. patent application Ser. No. 13/433,167, entitled TISSUE THICKNESSCOMPENSATORS, now U.S. Pat. No. 9,220,501;

U.S. patent application Ser. No. 13/433,175, entitled LAYERED TISSUETHICKNESS COMPENSATOR, now U.S. Pat. No. 9,332,974;

U.S. patent application Ser. No. 13/433,179, entitled TISSUE THICKNESSCOMPENSATORS FOR CIRCULAR SURGICAL STAPLERS, now U.S. Pat. No.9,364,233;

U.S. application Ser. No. 13/433,115, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING CAPSULES DEFINING A LOW PRESSURE ENVIRONMENT, nowU.S. Pat. No. 9,204,880;

U.S. patent application Ser. No. 13/433,118, entitled TISSUE THICKNESSCOMPENSATOR COMPRISED OF A PLURALITY OF MATERIALS, now U.S. Pat. No.9,414,838;

U.S. patent application Ser. No. 13/433,135, entitled MOVABLE MEMBER FORUSE WITH A TISSUE THICKNESS COMPENSATOR, now U.S. Pat. No. 9,517,063;

U.S. patent application Ser. No. 13/433,140, entitled TISSUE THICKNESSCOMPENSATOR AND METHOD FOR MAKING THE SAME, now U.S. Pat. No. 9,241,714;

U.S. patent application Ser. No. 13/433,147, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING CHANNELS, now U.S. Pat. No. 9,351,730;

U.S. patent application Ser. No. 13/433,126, entitled TISSUE THICKNESSCOMPENSATOR COMPRISING TISSUE INGROWTH FEATURES, now U.S. Pat. No.9,320,523; and

U.S. patent application Ser. No. 13/433,132, entitled DEVICES ANDMETHODS FOR ATTACHING TISSUE THICKNESS COMPENSATING MATERIALS TOSURGICAL STAPLING INSTRUMENTS, now U.S. Patent Application PublicationNo. 2013/0256373.

Certain exemplary embodiments will now be described to provide anoverall understanding of the principles of the structure, function,manufacture, and use of the devices and methods disclosed herein. One ormore examples of these embodiments are illustrated in the accompanyingdrawings. Those of ordinary skill in the art will understand that thedevices and methods specifically described herein and illustrated in theaccompanying drawings are non-limiting exemplary embodiments and thatthe scope of the various embodiments of the present invention is definedsolely by the claims. The features illustrated or described inconnection with one exemplary embodiment may be combined with thefeatures of other embodiments. Such modifications and variations areintended to be included within the scope of the present invention.

Reference throughout the specification to “various embodiments,” “someembodiments,” “one embodiment,” or “an embodiment”, or the like, meansthat a particular feature, structure, or characteristic described inconnection with the embodiment is included in at least one embodiment.Thus, appearances of the phrases “in various embodiments,” “in someembodiments,” “in one embodiment”, or “in an embodiment”, or the like,in places throughout the specification are not necessarily all referringto the same embodiment. Furthermore, the particular features,structures, or characteristics may be combined in any suitable manner inone or more embodiments. Thus, the particular features, structures, orcharacteristics illustrated or described in connection with oneembodiment may be combined, in whole or in part, with the featuresstructures, or characteristics of one or more other embodiments withoutlimitation. Such modifications and variations are intended to beincluded within the scope of the present invention.

The terms “proximal” and “distal” are used herein with reference to aclinician manipulating the handle portion of the surgical instrument.The term “proximal” referring to the portion closest to the clinicianand the term “distal” referring to the portion located away from theclinician. It will be further appreciated that, for convenience andclarity, spatial terms such as “vertical”, “horizontal”, “up”, and“down” may be used herein with respect to the drawings. However,surgical instruments are used in many orientations and positions, andthese terms are not intended to be limiting and/or absolute.

Various exemplary devices and methods are provided for performinglaparoscopic and minimally invasive surgical procedures. However, theperson of ordinary skill in the art will readily appreciate that thevarious methods and devices disclosed herein can be used in numeroussurgical procedures and applications including, for example, inconnection with open surgical procedures. As the present DetailedDescription proceeds, those of ordinary skill in the art will furtherappreciate that the various instruments disclosed herein can be insertedinto a body in any way, such as through a natural orifice, through anincision or puncture hole formed in tissue, etc. The working portions orend effector portions of the instruments can be inserted directly into apatient's body or can be inserted through an access device that has aworking channel through which the end effector and elongated shaft of asurgical instrument can be advanced.

Turning to the Drawings wherein like numerals denote like componentsthroughout the several views, FIG. 1 depicts a surgical instrument 10that is capable of practicing several unique benefits. The surgicalstapling instrument 10 is designed to manipulate and/or actuate variousforms and sizes of end effectors 12 that are operably attached thereto.In the embodiment depicted in FIGS. 1-1E, for example, the end effector12 includes an elongated channel 14 that forms a lower jaw 13 of the endeffector 12. The elongated channel 14 is configured to support an“implantable” staple cartridge 30 and also movably support an anvil 20that functions as an upper jaw 15 of the end effector 12.

In various embodiments, the elongated channel 14 may be fabricated from,for example, 300 & 400 Series, 17-4 & 17-7 stainless steel, titanium,etc. and be formed with spaced side walls 16. The anvil 20 may befabricated from, for example, 300 & 400 Series, 17-4 & 17-7 stainlesssteel, titanium, etc. and have a staple forming undersurface, generallylabeled as 22 that has a plurality of staple forming pockets 23 formedtherein. See FIGS. 1B-1E. In addition, the anvil 20 has a bifurcatedramp assembly 24 that protrudes proximally therefrom. An anvil pin 26protrudes from each lateral side of the ramp assembly 24 to be receivedwithin a corresponding slot or opening 18 in the side walls 16 of theelongated channel 14 to facilitate its movable or pivotable attachmentthereto.

Various forms of implantable staple cartridges may be employed with thevarious embodiments of the surgical instruments disclosed herein.Specific staple cartridge configurations and constructions will bediscussed in further detail below. However, in the embodiment depictedin FIG. 1A, an implantable staple cartridge 30 is shown. In at least oneembodiment, the staple cartridge 30 has a body portion 31 that consistsof a compressible hemostat material such as, for example, oxidizedregenerated cellulose (“ORC”) or a bio-absorbable foam in which lines ofunformed metal staples 32 are supported. In at least some embodiments,in order to prevent the staple from being affected and the hemostatmaterial from being activated during the introduction and positioningprocess, the entire cartridge may be coated or wrapped in abiodegradable film 38 such as a polydioxanon film sold under thetrademark PDS® or with a Polyglycerol sebacate (PGS) film or otherbiodegradable films formed from PGA (Polyglycolic acid, marketed underthe trade mark Vicryl), PCL (Polycaprolactone), PLA or PLLA (Polylacticacid), PHA (polyhydroxyalkanoate), PGCL (poliglecaprone 25, sold underthe trademark Monocryl) or a composite of PGA, PCL, PLA, PDS that wouldbe impermeable until ruptured. The body 31 of staple cartridge 30 issized to be removably supported within the elongated channel 14 as shownsuch that each staple 32 therein is aligned with corresponding stapleforming pockets 23 in the anvil when the anvil 20 is driven into formingcontact with the staple cartridge 30.

In use, once the end effector 12 has been positioned adjacent the targettissue, the end effector 12 is manipulated to capture or clamp thetarget tissue between an upper face 36 of the staple cartridge 30 andthe staple forming surface 22 of the anvil 20. The staples 32 are formedby moving the anvil 20 in a path that is substantially parallel to theelongated channel 14 to bring the staple forming surface 22 and, moreparticularly, the staple forming pockets 23 therein into substantiallysimultaneous contact with the upper face 36 of the staple cartridge 30.As the anvil 20 continues to move into the staple cartridge 30, the legs34 of the staples 32 contact a corresponding staple forming pocket 23 inanvil 20 which serves to bend the staple legs 34 over to form thestaples 32 into a “B shape”. Further movement of the anvil 20 toward theelongated channel 14 will further compress and form the staples 32 to adesired final formed height “FF”.

The above-described staple forming process is generally depicted inFIGS. 1B-1E. For example, FIG. 1B illustrates the end effector 12 withtarget tissue “T” between the anvil 20 and the upper face 36 of theimplantable staple cartridge 30. FIG. 1C illustrates the initialclamping position of the anvil 20 wherein the anvil has 20 been closedonto the target tissue “T” to clamp the target tissue “T” between theanvil 20 and the upper face 36 of the staple cartridge 30. FIG. 1Dillustrates the initial staple formation wherein the anvil 20 hasstarted to compress the staple cartridge 30 such that the legs 34 of thestaples 32 are starting to be formed by the staple forming pockets 23 inthe anvil 20. FIG. 1E illustrates the staple 32 in its final formedcondition through the target tissue “T” with the anvil 20 removed forclarity purposes. Once the staples 32 have been formed and fastened tothe target tissue “T”, the surgeon will move the anvil 20 to the openposition to enable the cartridge body 31 and the staples 32 to remainaffixed to the target tissue while the end effector 12 is beingwithdrawn from the patient. The end effector 12 forms all of the staplessimultaneously as the two jaws 13, 15 are clamped together. Theremaining “crushed” body materials 31 act as both a hemostat (the ORC)and a staple line reinforcement (PGA, PDS or any of the other filmcompositions mentioned above 38). Also, since the staples 32 never haveto leave the cartridge body 31 during forming, the likelihood of thestaples 32 being malformed during forming is minimized. As used hereinthe term “implantable” means that, in addition to the staples, thecartridge body materials that support the staples will also remain inthe patient and may eventually be absorbed by the patient's body. Suchimplantable staple cartridges are distinguishable from prior cartridgearrangements that remain positioned within the end effector in theirentirety after they have been fired.

In various implementations, the end effector 12 is configured to becoupled to an elongated shaft assembly 40 that protrudes from a handleassembly 100. The end effector 12 (when closed) and the elongated shaftassembly 40 may have similar cross-sectional shapes and be sized tooperably pass through a trocar tube or working channel in another formof access instrument. As used herein, the term “operably pass” meansthat the end effector and at least a portion of the elongated shaftassembly may be inserted through or passed through the channel or tubeopening and can be manipulated therein as needed to complete thesurgical stapling procedure. In some embodiments, when in a closedposition, the jaws 13 and 15 of the end effector 12 may provide the endeffector with a roughly circular cross-sectional shape that facilitatesits passage through a circular passage/opening. However, the endeffectors of various embodiments of the present invention, as well asthe elongated shaft assembly embodiments, could conceivably be providedwith other cross-sectional shapes that could otherwise pass throughaccess passages and openings that have non-circular cross-sectionalshapes. Thus, an overall size of a cross-section of a closed endeffector will be related to the size of the passage or opening throughwhich it is intended to pass. Thus, one end effector for example, may bereferred to as a “5 mm” end effector which means it can operably passthrough an opening that is at least approximately 5 mm in diameter.

In various embodiments, the elongated shaft assembly 40 may have anouter diameter that is substantially the same as the outer diameter ofthe end effector 12 when in a closed position. For example, a 5 mm endeffector may be coupled to an elongated shaft assembly 40 that has 5 mmcross-sectional diameter. However, as the present Detailed Descriptionproceeds, it will become apparent that various embodiments of thepresent may be effectively used in connection with different sizes ofend effectors. For example, a 10 mm end effector may be attached to anelongated shaft that has a 5 mm cross-sectional diameter. Conversely,for those applications wherein a 10 mm or larger access opening orpassage is provided, the elongated shaft assembly 40 may have a 10 mm(or larger) cross-sectional diameter, but may also be able to actuate a5 mm or 10 mm end effector. Accordingly, the outer shaft 40 may have anouter diameter that is the same as or is different from the outerdiameter of a closed end effector 12 attached thereto.

As depicted, the elongated shaft assembly 40 extends distally from thehandle assembly 100 in a generally straight line to define alongitudinal axis A-A. In various embodiments, for example, theelongated shaft assembly 40 may be approximately 9-16 inches (229-406mm) long. However, the elongated shaft assembly 40 may be provided inother lengths and, in other embodiments, may have joints therein or beotherwise configured to facilitate articulation of the end effector 12relative to other portions of the shaft or handle assembly as will bediscussed in further detail below. In various embodiments, the elongatedshaft assembly 40 includes a spine member 50 that extends from thehandle assembly 100 to the end effector 12. The proximal end of theelongated channel 14 of the end effector 12 has a pair of retentiontrunnions 17 protruding therefrom that are sized to be received withincorresponding trunnion openings or cradles 52 that are provided in adistal end of the spine member 50 to enable the end effector 12 to beremovably coupled the elongated shaft assembly 40. The spine member 50may be fabricated from, for example, 6061 or 7075 aluminum, stainlesssteel, titanium, etc.

In various embodiments, the handle assembly 100 comprises a pistolgrip-type housing that may be fabricated in two or more pieces forassembly purposes. For example, the handle assembly 100 as showncomprises a right hand case member 102 and a left hand case member (notillustrated) that are molded or otherwise fabricated from a polymer orplastic material and are designed to mate together. Such case membersmay be attached together by snap features, pegs and sockets molded orotherwise formed therein and/or by adhesive, screws, etc. The spinemember 50 has a proximal end 54 that has a flange 56 formed thereon. Theflange 56 is configured to be rotatably supported within a groove 106formed by mating ribs 108 that protrude inwardly from each of the casemembers 102, 104. Such arrangement facilitates the attachment of thespine member 50 to the handle assembly 100 while enabling the spinemember 50 to be rotated relative to the handle assembly 100 about thelongitudinal axis A-A in a 360° path.

As can be further seen in FIG. 1, the spine member 50 passes through andis supported by a mounting bushing 60 that is rotatably affixed to thehandle assembly 100. The mounting bushing 60 has a proximal flange 62and a distal flange 64 that define a rotational groove 65 that isconfigured to rotatably receive a nose portion 101 of the handleassembly 100 therebetween. Such arrangement enables the mounting bushing60 to rotate about longitudinal axis A-A relative to the handle assembly100. The spine member 50 is non-rotatably pinned to the mounting bushing60 by a spine pin 66. In addition, a rotation knob 70 is attached to themounting bushing 60. In one embodiment, for example, the rotation knob70 has a hollow mounting flange portion 72 that is sized to receive aportion of the mounting bushing 60 therein. In various embodiments, therotation knob 70 may be fabricated from, for example, glass or carbonfilled Nylon, polycarbonate, Ultem®, etc. and is affixed to the mountingbushing 60 by the spine pin 66 as well. In addition, an inwardlyprotruding retention flange 74 is formed on the mounting flange portion72 and is configured to extend into a radial groove 68 formed in themounting bushing 60. Thus, the surgeon may rotate the spine member 50(and the end effector 12 attached thereto) about longitudinal axis A-Ain a 360° path by grasping the rotation knob 70 and rotating it relativeto the handle assembly 100.

In various embodiments, the anvil 20 is retained in an open position byan anvil spring 21 and/or another biasing arrangement. The anvil 20 isselectively movable from the open position to various closed or clampingand firing positions by a firing system, generally designated as 109.The firing system 109 includes a “firing member” 110 which, in variousembodiments, comprises a hollow firing tube 110. The hollow firing tube110 is axially movable on the spine member 50 and thus forms the outerportion of the elongated shaft assembly 40. The firing tube 110 may befabricated from a polymer or other suitable material and have a proximalend that is attached to a firing yoke 114 of the firing system 109. Invarious embodiments for example, the firing yoke 114 may be over-moldedto the proximal end of the firing tube 110. However, other fastenerarrangements may be employed.

As can be seen in FIG. 1, the firing yoke 114 may be rotatably supportedwithin a support collar 120 that is configured to move axially withinthe handle assembly 100. In various embodiments, the support collar 120has a pair of laterally extending fins that are sized to be slidablyreceived within fin slots formed in the right and left hand casemembers. Thus, the support collar 120 may slide axially within thehandle housing 100 while enabling the firing yoke 114 and firing tube110 to rotate relative thereto about the longitudinal axis A-A. Invarious embodiments, a longitudinal slot is provided through the firingtube 110 to enable the spine pin 66 to extend therethrough into thespine member 50 while facilitating the axial travel of the firing tube110 on the spine member 50.

The firing system 109 further comprises a firing trigger 130 whichserves to control the axial travel of the firing tube 110 on the spinemember 50. See FIG. 1. Such axial movement in the distal direction ofthe firing tube 110 into firing interaction with the anvil 20 isreferred to herein as “firing motion”. As can be seen in FIG. 1, thefiring trigger 130 is movably or pivotally coupled to the handleassembly 100 by a pivot pin 132. A torsion spring 135 is employed tobias the firing trigger 130 away from the pistol grip portion 107 of thehandle assembly 100 to an un-actuated “open” or starting position. Ascan be seen in FIG. 1, the firing trigger 130 has an upper portion 134that is movably attached to (pinned) firing links 136 that are movablyattached to (pinned) the support collar 120. Thus, movement of thefiring trigger 130 from the starting position (FIG. 1) toward an endingposition adjacent the pistol grip portion 107 of the handle assembly 100will cause the firing yoke 114 and the firing tube 110 to move in thedistal direction “DD”. Movement of the firing trigger 130 away from thepistol grip portion 107 of the handle assembly 100 (under the bias ofthe torsion spring 135) will cause the firing yoke 114 and firing tube110 to move in the proximal direction “PD” on the spine member 50.

Various embodiments of the present invention may be employed withdifferent sizes and configurations of implantable staple cartridges. Forexample, the surgical instrument 10, when used in connection with afirst firing adapter 140, may be used with a 5 mm end effector 12 thatis approximately 20 mm long (or in other lengths) which supports animplantable staple cartridge 30. Such end effector size may beparticularly well-suited, for example, to complete relatively finedissection and vascular transactions. However, as will be discussed infurther detail below, the surgical instrument 10 may also be employed,for example, in connection with other sizes of end effectors and staplecartridges by replacing the first firing adapter 140 with a secondfiring adapter. In still other embodiments, the elongated shaft assembly40 may configured to be attached to only one form or size of endeffector.

One method of removably coupling the end effector 12 to the spine member50 will now be explained. The coupling process is commenced by insertingthe retention trunnions 17 on the elongated channel 14 into the trunnioncradles 52 in the spine member 50. Thereafter, the surgeon advances thefiring trigger 130 toward the pistol grip 107 of the housing assembly100 to distally advance the firing tube 110 and the first firing adapter140 over a proximal end portion 47 of the elongated channel 14 tothereby retain the trunnions 17 in their respective cradles 52. Suchposition of the first firing adapter 140 over the trunnions 17 isreferred to herein as the “coupled position”. Various embodiments of thepresent invention may also have an end effector locking assembly forlocking the firing trigger 130 in position after an end effector 12 hasbeen attached to the spine member 50.

More specifically, one embodiment of the end effector locking assembly160 includes a retention pin 162 that is movably supported in the upperportion 134 of the firing trigger 130. As discussed above, the firingtube 110 must initially be advanced distally to the coupled positionwherein the first firing adapter 140 retains the retention trunnions 17of the end effector 12 in the trunnion cradles 52 in the spine member50. The surgeon advances the firing adapter 140 distally to the coupledposition by pulling the firing trigger 130 from the starting positiontoward the pistol grip 107. As the firing trigger 130 is initiallyactuated, the retention pin 162 is moved distally until the firing tube110 has advanced the first firing adapter 140 to the coupled position atwhich point the retention pin 162 is biased into a locking cavity 164formed in the case member. In various embodiments, when the retentionpin 162 enters into the locking cavity 164, the pin 162 may make anaudible “click” or other sound, as well as provide a tactile indicationto the surgeon that the end effector 12 has been “locked” onto the spinemember 50. In addition, the surgeon cannot inadvertently continue toactuate the firing trigger 130 to start to form staples 32 in the endeffector 12 without intentionally biasing the retention pin 162 out ofthe locking cavity 164. Similarly, if the surgeon releases the firingtrigger 130 when in the coupled position, it is retained in thatposition by the retention pin 162 to prevent the firing trigger 130 fromreturning to the starting position and thereby releasing the endeffector 12 from the spine member 50.

Various embodiments of the present invention may further include afiring system lock button 137 that is pivotally attached to the handleassembly 100. In one form, the firing system lock button 137 has a latch138 formed on a distal end thereof that is oriented to engage the firingyoke 114 when the firing release button is in a first latching position.As can be seen in FIG. 1, a latch spring 139 serves to bias the firingsystem lock button 137 to the first latching position. In variouscircumstances, the latch 138 serves to engage the firing yoke 114 at apoint where the position of the firing yoke 114 on the spine member 50corresponds to a point wherein the first firing adapter 140 is about todistally advance up the clamping ramp 28 on the anvil 20. It will beunderstood that, as the first firing adapter 140 advances axially up theclamping ramp 28, the anvil 20 will move in a path such that its stapleforming surface portion 22 is substantially parallel to the upper face36 of the staple cartridge 30.

After the end effector 12 has been coupled to the spine member 50, thestaple forming process is commenced by first depressing the firingsystem lock button 137 to enable the firing yoke 114 to be further moveddistally on the spine member 50 and ultimately compress the anvil 20into the staple cartridge 30. After depressing the firing system lockbutton 137, the surgeon continues to actuate the firing trigger 130towards the pistol grip 107 thereby driving the first staple collar 140up the corresponding staple forming ramp 29 to force the anvil 20 intoforming contact with the staples 32 in the staple cartridge 30. Thefiring system lock button 137 prevents the inadvertent forming of thestaples 32 until the surgeon is ready to start that process. In thisembodiment, the surgeon must depress the firing system lock button 137before the firing trigger 130 may be further actuated to begin thestaple forming process.

The surgical instrument 10 may be solely used as a tissue staplingdevice if so desired. However, various embodiments of the presentinvention may also include a tissue cutting system, generally designatedas 170. In at least one form, the tissue cutting system 170 comprises aknife member 172 that may be selectively advanced from an un-actuatedposition adjacent the proximal end of the end effector 12 to an actuatedposition by actuating a knife advancement trigger 200. The knife member172 is movably supported within the spine member 50 and is attached orotherwise protrudes from a knife rod 180. The knife member 172 may befabricated from, for example, 420 or 440 stainless steel with a hardnessof greater than 38HRC (Rockwell Hardness C-scale) and have a tissuecutting edge 176 formed on the distal end 174 thereof and be configuredto slidably extend through a slot in the anvil 20 and a centrallydisposed slot 33 in the staple cartridge 30 to cut through tissue thatis clamped in the end effector 12. In various embodiments, the knife rod180 extends through the spine member 50 and has a proximal end portionwhich drivingly interfaces with a knife transmission that is operablyattached to the knife advance trigger 200. In various embodiments, theknife advance trigger 200 is attached to pivot pin 132 such that it maybe pivoted or otherwise actuated without actuating the firing trigger130. In various embodiments, a first knife gear 192 is also attached tothe pivot pin 132 such that actuation of the knife advance trigger 200also pivots the first knife gear 192. A firing return spring 202 isattached between the first knife gear 192 and the handle housing 100 tobias the knife advancement trigger 200 to a starting or un-actuatedposition.

Various embodiments of the knife transmission also include a secondknife gear 194 that is rotatably supported on a second gear spindle andin meshing engagement with the first knife gear 192. The second knifegear 194 is in meshing engagement with a third knife gear 196 that issupported on a third gear spindle. Also supported on the third gearspindle 195 is a fourth knife gear 198. The fourth knife gear 198 isadapted to drivingly engage a series of annular gear teeth or rings on aproximal end of the knife rod 180. Thus, such arrangement enables thefourth knife gear 198 to axially drive the knife rod 180 in the distaldirection “DD” or proximal direction “PD” while enabling the firing rod180 to rotate about longitudinal axis A-A with respect to the fourthknife gear 198. Accordingly, the surgeon may axially advance the firingrod 180 and ultimately the knife member 172 distally by pulling theknife advancement trigger 200 towards the pistol grip 107 of the handleassembly 100.

Various embodiments of the present invention further include a knifelockout system 210 that prevents the advancement of the knife member 172unless the firing trigger 130 has been pulled to the fully firedposition. Such feature will therefore prevent the activation of theknife advancement system 170 unless the staples have first been fired orformed into the tissue. As can be seen in FIG. 1, variousimplementations of the knife lockout system 210 comprise a knife lockoutbar 211 that is pivotally supported within the pistol grip portion 107of the handle assembly 100. The knife lockout bar 211 has an activationend 212 that is adapted to be engaged by the firing trigger 130 when thefiring trigger 130 is in the fully fired position. In addition, theknife lockout bar 211 has a retaining hook 214 on its other end that isadapted to hookingly engage a latch rod 216 on the first cut gear 192. Aknife lock spring 218 is employed to bias the knife lockout bar 211 to a“locked” position wherein the retaining hook 214 is retained inengagement with the latch rod 216 to thereby prevent actuation of theknife advancement trigger 200 unless the firing trigger 130 is in thefully fired position.

After the staples have been “fired” (formed) into the target tissue, thesurgeon may depress the firing trigger release button 167 to enable thefiring trigger 130 to return to the starting position under the bias ofthe torsion spring 135 which enables the anvil 20 to be biased to anopen position under the bias of spring 21. When in the open position,the surgeon may withdraw the end effector 12 leaving the implantablestaple cartridge 30 and staples 32 behind. In applications wherein theend effector was inserted through a passage, working channel, etc. thesurgeon will return the anvil 20 to the closed position by activatingthe firing trigger 130 to enable the end effector 12 to be withdrawn outthrough the passage or working channel. If, however, the surgeon desiresto cut the target tissue after firing the staples, the surgeon activatesthe knife advancement trigger 200 in the above-described manner to drivethe knife bar 172 through the target tissue to the end of the endeffector. Thereafter, the surgeon may release the knife advancementtrigger 200 to enable the firing return spring 202 to cause the firingtransmission to return the knife bar 172 to the starting (un-actuated)position. Once the knife bar 172 has been returned to the startingposition, the surgeon may open the end effector jaws 13, 15 to releasethe implantable cartridge 30 within the patient and then withdraw theend effector 12 from the patient. Thus, such surgical instrumentsfacilitate the use of small implantable staple cartridges that may beinserted through relatively smaller working channels and passages, whileproviding the surgeon with the option to fire the staples withoutcutting tissue or if desired to also cut tissue after the staples havebeen fired.

Various unique and novel embodiments of the present invention employ acompressible staple cartridge that supports staples in a substantiallystationary position for forming contact by the anvil. In variousembodiments, the anvil is driven into the unformed staples wherein, inat least one such embodiment, the degree of staple formation attained isdependent upon how far the anvil is driven into the staples. Such anarrangement provides the surgeon with the ability to adjust the amountof forming or firing pressure applied to the staples and thereby alterthe final formed height of the staples. In other various embodiments ofthe present invention, surgical stapling arrangements can employ stapledriving elements which can lift the staples toward the anvil. Suchembodiments are described in greater detail further below.

In various embodiments, with regard to the embodiments described indetail above, the amount of firing motion that is applied to the movableanvil is dependent upon the degree of actuation of the firing trigger.For example, if the surgeon desires to attain only partially formedstaples, then the firing trigger is only partially depressed inwardtowards the pistol grip 107. To attain more staple formation, thesurgeon simply compresses the firing trigger further which results inthe anvil being further driven into forming contact with the staples. Asused herein, the term “forming contact” means that the staple formingsurface or staple forming pockets have contacted the ends of the staplelegs and have started to form or bend the legs over into a formedposition. The degree of staple formation refers to how far the staplelegs have been folded over and ultimately relates to the forming heightof the staple as referenced above. Those of ordinary skill in the artwill further understand that, because the anvil 20 moves in asubstantially parallel relationship with respect to the staple cartridgeas the firing motions are applied thereto, the staples are formedsubstantially simultaneously with substantially the same formed heights.

FIGS. 2 and 3 illustrate an alternative end effector 12″ that is similarto the end effector 12′ described above, except with the followingdifferences that are configured to accommodate a knife bar 172′. Theknife bar 172′ is coupled to or protrudes from a knife rod 180 and isotherwise operated in the above described manner with respect to theknife bar 172. However, in this embodiment, the knife bar 172′ is longenough to traverse the entire length of the end effector 12″ andtherefore, a separate distal knife member is not employed in the endeffector 12″. The knife bar 172′ has an upper transverse member 173′ anda lower transverse member 175′ formed thereon. The upper transversemember 173′ is oriented to slidably transverse a corresponding elongatedslot 250 in anvil 20″ and the lower transverse member 175′ is orientedto traverse an elongated slot 252 in the elongated channel 14″ of theend effector 12″. A disengagement slot (not shown) is also provide dinthe anvil 20″ such that when the knife bar 172′ has been driven to anending position with thin end effector 12″, the upper transverse member173′ drops through the corresponding slot to enable the anvil 20″ tomove to the open position to disengage the stapled and cut tissue. Theanvil 20″ may be otherwise identical to anvil 20 described above and theelongated channel 14″ may be otherwise identical to elongated channel 14described above.

In these embodiments, the anvil 20″ is biased to a fully open position(FIG. 2) by a spring or other opening arrangement (not shown). The anvil20″ is moved between the open and fully clamped positions by the axialtravel of the firing adapter 150 in the manner described above. Once thefiring adapter 150 has been advanced to the fully clamped position (FIG.3), the surgeon may then advance the knife bar 172″ distally in themanner described above. If the surgeon desires to use the end effectoras a grasping device to manipulate tissue, the firing adapter may bemoved proximally to allow the anvil 20″ to move away from the elongatedchannel 14″ as represented in FIG. 4 in broken lines. In thisembodiment, as the knife bar 172″ moves distally, the upper transversemember 173′ and the lower transverse member 175′ draw the anvil 20″ andelongated channel 14″ together to achieve the desired staple formationas the knife bar 172″ is advanced distally through the end effector 12″.See FIG. 5. Thus, in this embodiment, staple formation occurssimultaneously with tissue cutting, but the staples themselves may besequentially formed as the knife bar 172″ is driven distally.

The unique and novel features of the various surgical staple cartridgesand the surgical instruments of the present invention enable the staplesin those cartridges to be arranged in one or more linear or non-linearlines. A plurality of such staple lines may be provided on each side ofan elongated slot that is centrally disposed within the staple cartridgefor receiving the tissue cutting member therethrough. In onearrangement, for example, the staples in one line may be substantiallyparallel with the staples in adjacent line(s) of staples, but offsettherefrom. In still other embodiments, one or more lines of staples maybe non-linear in nature. That is, the base of at least one staple in aline of staples may extend along an axis that is substantiallytransverse to the bases of other staples in the same staple line. Forexample, the lines of staples on each side of the elongated slot mayhave a zigzag appearance.

In various embodiments, a staple cartridge can comprise a cartridge bodyand a plurality of staples stored within the cartridge body. In use, thestaple cartridge can be introduced into a surgical site and positionedon a side of the tissue being treated. In addition, a staple-forminganvil can be positioned on the opposite side of the tissue. In variousembodiments, the anvil can be carried by a first jaw and the staplecartridge can be carried by a second jaw, wherein the first jaw and/orthe second jaw can be moved toward the other. Once the staple cartridgeand the anvil have been positioned relative to the tissue, the staplescan be ejected from the staple cartridge body such that the staples canpierce the tissue and contact the staple-forming anvil. Once the stapleshave been deployed from the staple cartridge body, the staple cartridgebody can then be removed from the surgical site. In various embodimentsdisclosed herein, a staple cartridge, or at least a portion of a staplecartridge, can be implanted with the staples. In at least one suchembodiment, as described in greater detail further below, a staplecartridge can comprise a cartridge body which can be compressed,crushed, and/or collapsed by the anvil when the anvil is moved from anopen position into a closed position. When the cartridge body iscompressed, crushed, and/or collapsed, the staples positioned within thecartridge body can be deformed by the anvil. Alternatively, the jawsupporting the staple cartridge can be moved toward the anvil into aclosed position. In either event, in various embodiments, the staplescan be deformed while they are at least partially positioned within thecartridge body. In certain embodiments, the staples may not be ejectedfrom the staple cartridge while, in some embodiments, the staples can beejected from the staple cartridge along with a portion of the cartridgebody.

Referring now to FIGS. 6A-6D, a compressible staple cartridge, such asstaple cartridge 1000, for example, can comprise a compressible,implantable cartridge body 1010 and, in addition, a plurality of staples1020 positioned in the compressible cartridge body 1010, although onlyone staple 1020 is depicted in FIGS. 6A-6D. FIG. 6A illustrates thestaple cartridge 1000 supported by a staple cartridge support, or staplecartridge channel, 1030, wherein the staple cartridge 1000 isillustrated in an uncompressed condition. In such an uncompressedcondition, the anvil 1040 may or may not be in contact with the tissueT. In use, the anvil 1040 can be moved from an open position intocontact with the tissue T as illustrated in FIG. 6B and position thetissue T against the cartridge body 1010. Even though the anvil 1040 canposition the tissue T against a tissue-contacting surface 1019 of staplecartridge body 1010, referring again to FIG. 6B, the staple cartridgebody 1010 may be subjected to little, if any, compressive force orpressure at such point and the staples 1020 may remain in an unformed,or unfired, condition. As illustrated in FIGS. 6A and 6B, the staplecartridge body 1010 can comprise one or more layers and the staple legs1021 of staples 1020 can extend upwardly through these layers. Invarious embodiments, the cartridge body 1010 can comprise a first layer1011, a second layer 1012, a third layer 1013, wherein the second layer1012 can be positioned intermediate the first layer 1011 and the thirdlayer 1013, and a fourth layer 1014, wherein the third layer 1013 can bepositioned intermediate the second layer 1012 and the fourth layer 1014.In at least one embodiment, the bases 1022 of the staples 1020 can bepositioned within cavities 1015 in the fourth layer 1014 and the staplelegs 1021 can extend upwardly from the bases 1022 and through the fourthlayer 1014, the third layer 1013, and the second layer 1012, forexample. In various embodiments, each deformable leg 1021 can comprise atip, such as sharp tip 1023, for example, which can be positioned in thesecond layer 1012, for example, when the staple cartridge 1000 is in anuncompressed condition. In at least one such embodiment, the tips 1023may not extend into and/or through the first layer 1011, wherein, in atleast one embodiment, the tips 1023 may not protrude through thetissue-contacting surface 1019 when the staple cartridge 1000 is in anuncompressed condition. In certain other embodiments, the sharp tips1023 may be positioned in the third layer 1013, and/or any othersuitable layer, when the staple cartridge is in an uncompressedcondition. In various alternative embodiments, a cartridge body of astaple cartridge may have any suitable number of layers such as lessthan four layers or more than four layers, for example.

In various embodiments, as described in greater detail below, the firstlayer 1011 can be comprised of a buttress material and/or plasticmaterial, such as polydioxanone (PDS) and/or polyglycolic acid (PGA),for example, and the second layer 1012 can be comprised of abioabsorbable foam material and/or a compressible haemostatic material,such as oxidized regenerated cellulose (ORC), for example. In variousembodiments, one or more of the first layer 1011, the second layer 1012,the third layer 1013, and the fourth layer 1014 may hold the staples1020 within the staple cartridge body 1010 and, in addition, maintainthe staples 1020 in alignment with one another. In various embodiments,the third layer 1013 can be comprised of a buttress material, or afairly incompressible or inelastic material, which can be configured tohold the staple legs 1021 of the staples 1020 in position relative toone another. Furthermore, the second layer 1012 and the fourth layer1014, which are positioned on opposite sides of the third layer 1013,can stabilize, or reduce the movement of, the staples 1020 even thoughthe second layer 1012 and the fourth layer 1014 can be comprised of acompressible foam or elastic material. In certain embodiments, thestaple tips 1023 of the staple legs 1021 can be at least partiallyembedded in the first layer 1011. In at least one such embodiment, thefirst layer 1011 and the third layer 1013 can be configured toco-operatively and firmly hold the staple legs 1021 in position. In atleast one embodiment, the first layer 1011 and the third layer 1013 caneach be comprised of a sheet of bioabsorbable plastic, such aspolyglycolic acid (PGA) which is marketed under the trade name Vicryl,polylactic acid (PLA or PLLA), polydioxanone (PDS), polyhydroxyalkanoate(PHA), poliglecaprone 25 (PGCL) which is marketed under the trade nameMonocryl, polycaprolactone (PCL), and/or a composite of PGA, PLA, PDS,PHA, PGCL and/or PCL, for example, and the second layer 1012 and thefourth layer 1014 can each be comprised of at least one haemostaticmaterial or agent.

Although the first layer 1011 can be compressible, the second layer 1012can be substantially more compressible than the first layer 1011. Forexample, the second layer 1012 can be about twice as compressible, aboutthree times as compressible, about four times as compressible, aboutfive times as compressible, and/or about ten times as compressible, forexample, as the first layer 1011. Stated another way, the second layer1012 may compress about two times, about three times, about four times,about five times, and/or about ten times as much as first layer 1011,for a given force. In certain embodiments, the second layer 1012 can bebetween about twice as compressible and about ten times as compressible,for example, as the first layer 1011. In at least one embodiment, thesecond layer 1012 can comprise a plurality of air voids defined therein,wherein the amount and/or size of the air voids in the second layer 1012can be controlled in order to provide a desired compressibility of thesecond layer 1012. Similar to the above, although the third layer 1013can be compressible, the fourth layer 1014 can be substantially morecompressible than the third layer 1013. For example, the fourth layer1014 can be about twice as compressible, about three times ascompressible, about four times as compressible, about five times ascompressible, and/or about ten times as compressible, for example, asthe third layer 1013. Stated another way, the fourth layer 1014 maycompress about two times, about three times, about four times, aboutfive times, and/or about ten times as much as third layer 1013, for agiven force. In certain embodiments, the fourth layer 1014 can bebetween about twice as compressible and about ten times as compressible,for example, as the third layer 1013. In at least one embodiment, thefourth layer 1014 can comprise a plurality of air voids defined therein,wherein the amount and/or size of the air voids in the fourth layer 1014can be controlled in order to provide a desired compressibility of thefourth layer 1014. In various circumstances, the compressibility of acartridge body, or cartridge body layer, can be expressed in terms of acompression rate, i.e., a distance in which a layer is compressed for agiven amount of force. For example, a layer having a high compressionrate will compress a larger distance for a given amount of compressiveforce applied to the layer as compared to a layer having a lowercompression rate. This being said, the second layer 1012 can have ahigher compression rate than the first layer 1011 and, similarly, thefourth layer 1014 can have a higher compression rate than the thirdlayer 1013. In various embodiments, the second layer 1012 and the fourthlayer 1014 can be comprised of the same material and can comprise thesame compression rate. In various embodiments, the second layer 1012 andthe fourth layer 1014 can be comprised of materials having differentcompression rates. Similarly, the first layer 1011 and the third layer1013 can be comprised of the same material and can comprise the samecompression rate. In certain embodiments, the first layer 1011 and thethird layer 1013 can be comprised of materials having differentcompression rates.

As the anvil 1040 is moved toward its closed position, the anvil 1040can contact tissue T and apply a compressive force to the tissue T andthe staple cartridge 1000, as illustrated in FIG. 6C. In suchcircumstances, the anvil 1040 can push the top surface, ortissue-contacting surface 1019, of the cartridge body 1010 downwardlytoward the staple cartridge support 1030. In various embodiments, thestaple cartridge support 1030 can comprise a cartridge support surface1031 which can be configured to support the staple cartridge 1000 as thestaple cartridge 1000 is compressed between the cartridge supportsurface 1031 and the tissue-contacting surface 1041 of anvil 1040. Owingto the pressure applied by the anvil 1040, the cartridge body 1010 canbe compressed and the anvil 1040 can come into contact with the staples1020. More particularly, in various embodiments, the compression of thecartridge body 1010 and the downward movement of the tissue-contactingsurface 1019 can cause the tips 1023 of the staple legs 1021 to piercethe first layer 1011 of cartridge body 1010, pierce the tissue T, andenter into forming pockets 1042 in the anvil 1040. As the cartridge body1010 is further compressed by the anvil 1040, the tips 1023 can contactthe walls defining the forming pockets 1042 and, as a result, the legs1021 can be deformed or curled inwardly, for example, as illustrated inFIG. 6C. As the staple legs 1021 are being deformed, as also illustratedin FIG. 6C, the bases 1022 of the staples 1020 can be in contact with orsupported by the staple cartridge support 1030. In various embodiments,as described in greater detail below, the staple cartridge support 1030can comprise a plurality of support features, such as staple supportgrooves, slots, or troughs 1032, for example, which can be configured tosupport the staples 1020, or at least the bases 1022 of the staples1020, as the staples 1020 are being deformed. As also illustrated inFIG. 6C, the cavities 1015 in the fourth layer 1014 can collapse as aresult of the compressive force applied to the staple cartridge body1010. In addition to the cavities 1015, the staple cartridge body 1010can further comprise one or more voids, such as voids 1016, for example,which may or may not comprise a portion of a staple positioned therein,that can be configured to allow the cartridge body 1010 to collapse. Invarious embodiments, the cavities 1015 and/or the voids 1016 can beconfigured to collapse such that the walls defining the cavities and/orwalls deflect downwardly and contact the cartridge support surface 1031and/or contact a layer of the cartridge body 1010 positioned underneaththe cavities and/or voids.

Upon comparing FIG. 6B and FIG. 6C, it is evident that the second layer1012 and the fourth layer 1014 have been substantially compressed by thecompressive pressure applied by the anvil 1040. It may also be notedthat the first layer 1011 and the third layer 1013 have been compressedas well. As the anvil 1040 is moved into its closed position, the anvil1040 may continue to further compress the cartridge body 1010 by pushingthe tissue-contacting surface 1019 downwardly toward the staplecartridge support 1030. As the cartridge body 1010 is furthercompressed, the anvil 1040 can deform the staples 1020 into theircompletely-formed shape as illustrated in FIG. 6D. Referring to FIG. 6D,the legs 1021 of each staple 1020 can be deformed downwardly toward thebase 1022 of each staple 1020 in order to capture at least a portion ofthe tissue T, the first layer 1011, the second layer 1012, the thirdlayer 1013, and the fourth layer 1014 between the deformable legs 1021and the base 1022. Upon comparing FIGS. 6C and 6D, it is further evidentthat the second layer 1012 and the fourth layer 1014 have been furthersubstantially compressed by the compressive pressure applied by theanvil 1040. It may also be noted upon comparing FIGS. 6C and 6D that thefirst layer 1011 and the third layer 1013 have been further compressedas well. After the staples 1020 have been completely, or at leastsufficiently, formed, the anvil 1040 can be lifted away from the tissueT and the staple cartridge support 1030 can be moved away, and/ordetached from, the staple cartridge 1000. As depicted in FIG. 6D, and asa result of the above, the cartridge body 1010 can be implanted with thestaples 1020. In various circumstances, the implanted cartridge body1010 can support the tissue along the staple line. In somecircumstances, a haemostatic agent, and/or any other suitabletherapeutic medicament, contained within the implanted cartridge body1010 can treat the tissue over time. A haemostatic agent, as mentionedabove, can reduce the bleeding of the stapled and/or incised tissuewhile a bonding agent or tissue adhesive can provide strength to thetissue over time. The implanted cartridge body 1010 can be comprised ofmaterials such as ORC (oxidized regenerated cellulose), extracellularproteins such as collagen, polyglycolic acid (PGA) which is marketedunder the trade name Vicryl, polylactic acid (PLA or PLLA),polydioxanone (PDS), polyhydroxyalkanoate (PHA), poliglecaprone 25(PGCL) which is marketed under the trade name Monocryl, polycaprolactone(PCL), and/or a composite of PGA, PLA, PDS, PHA, PGCL and/or PCL, forexample. In certain circumstances, the cartridge body 1010 can comprisean antibiotic and/or anti-microbial material, such as colloidal silverand/or triclosan, for example, which can reduce the possibility ofinfection in the surgical site.

In various embodiments, the layers of the cartridge body 1010 can beconnected to one another. In at least one embodiment, the second layer1012 can be adhered to the first layer 1011, the third layer 1013 can beadhered to the second layer 1012, and the fourth layer 1014 can beadhered to the third layer 1013 utilizing at least one adhesive, such asfibrin and/or protein hydrogel, for example. In certain embodiments,although not illustrated, the layers of the cartridge body 1010 can beconnected together by interlocking mechanical features. In at least onesuch embodiment, the first layer 1011 and the second layer 1012 can eachcomprise corresponding interlocking features, such as a tongue andgroove arrangement and/or a dovetail joint arrangement, for example.Similarly, the second layer 1012 and the third layer 1013 can eachcomprise corresponding interlocking features while the third layer 1013and the fourth layer 1014 can each comprise corresponding interlockingfeatures. In certain embodiments, although not illustrated, the staplecartridge 1000 can comprise one or more rivets, for example, which canextend through one or more layers of the cartridge body 1010. In atleast one such embodiment, each rivet can comprise a first end, or head,positioned adjacent to the first layer 1011 and a second head positionedadjacent to the fourth layer 1014 which can be either assembled to orformed by a second end of the rivet. Owing to the compressible nature ofthe cartridge body 1010, in at least one embodiment, the rivets cancompress the cartridge body 1010 such that the heads of the rivets canbe recessed relative to the tissue-contacting surface 1019 and/or thebottom surface 1018 of the cartridge body 1010, for example. In at leastone such embodiment, the rivets can be comprised of a bioabsorbablematerial, such as polyglycolic acid (PGA) which is marketed under thetrade name Vicryl, polylactic acid (PLA or PLLA), polydioxanone (PDS),polyhydroxyalkanoate (PHA), poliglecaprone 25 (PGCL) which is marketedunder the trade name Monocryl, polycaprolactone (PCL), and/or acomposite of PGA, PLA, PDS, PHA, PGCL and/or PCL, for example. Incertain embodiments, the layers of the cartridge body 1010 may not beconnected to one another other than by the staples 1020 containedtherein. In at least one such embodiment, the frictional engagementbetween the staple legs 1021 and the cartridge body 1010, for example,can hold the layers of the cartridge body 1010 together and, once thestaples have been formed, the layers can be captured within the staples1020. In certain embodiments, at least a portion of the staple legs 1021can comprise a roughened surface or rough coating which can increase thefriction forces between the staples 1020 and the cartridge body 1010.

As described above, a surgical instrument can comprise a first jawincluding the staple cartridge support 1030 and a second jaw includingthe anvil 1040. In various embodiments, as described in greater detailfurther below, the staple cartridge 1000 can comprise one or moreretention features which can be configured to engage the staplecartridge support 1030 and, as a result, releasably retain the staplecartridge 1000 to the staple cartridge support 1030. In certainembodiments, the staple cartridge 1000 can be adhered to the staplecartridge support 1030 by at least one adhesive, such as fibrin and/orprotein hydrogel, for example. In use, in at least one circumstance,especially in laparoscopic and/or endoscopic surgery, the second jaw canbe moved into a closed position opposite the first jaw, for example,such that the first and second jaws can be inserted through a trocarinto a surgical site. In at least one such embodiment, the trocar candefine an approximately 5 mm aperture, or cannula, through which thefirst and second jaws can be inserted. In certain embodiments, thesecond jaw can be moved into a partially-closed position intermediatethe open position and the closed position which can allow the first andsecond jaws to be inserted through the trocar without deforming thestaples 1020 contained in the staple cartridge body 1010. In at leastone such embodiment, the anvil 1040 may not apply a compressive force tothe staple cartridge body 1010 when the second jaw is in itspartially-closed intermediate position while, in certain otherembodiments, the anvil 1040 can compress the staple cartridge body 1010when the second jaw is in its partially-closed intermediate position.Even though the anvil 1040 can compress the staple cartridge body 1010when it is in such an intermediate position, the anvil 1040 may notsufficiently compress the staple cartridge body 1010 such that the anvil1040 comes into contact with the staples 1020 and/or such that thestaples 1020 are deformed by the anvil 1040. Once the first and secondjaws have been inserted through the trocar into the surgical site, thesecond jaw can be opened once again and the anvil 1040 and the staplecartridge 1000 can be positioned relative to the targeted tissue asdescribed above.

In various embodiments, referring now to FIGS. 7A-7D, an end effector ofa surgical stapler can comprise an implantable staple cartridge 1100positioned intermediate an anvil 1140 and a staple cartridge support1130. Similar to the above, the anvil 1140 can comprise atissue-contacting surface 1141, the staple cartridge 1100 can comprise atissue-contacting surface 1119, and the staple cartridge support 1130can comprise a support surface 1131 which can be configured to supportthe staple cartridge 1100. Referring to FIG. 7A, the anvil 1140 can beutilized to position the tissue T against the tissue contacting surface1119 of staple cartridge 1100 without deforming the staple cartridge1100 and, when the anvil 1140 is in such a position, thetissue-contacting surface 1141 can be positioned a distance 1101 a awayfrom the staple cartridge support surface 1131 and the tissue-contactingsurface 1119 can be positioned a distance 1102 a away from the staplecartridge support surface 1131. Thereafter, as the anvil 1140 is movedtoward the staple cartridge support 1130, referring now to FIG. 7B, theanvil 1140 can push the top surface, or tissue-contacting surface 1119,of staple cartridge 1100 downwardly and compress the first layer 1111and the second layer 1112 of cartridge body 1110. As the layers 1111 and1112 are compressed, referring again to FIG. 7B, the second layer 1112can be crushed and the legs 1121 of staples 1120 can pierce the firstlayer 1111 and enter into the tissue T. In at least one such embodiment,the staples 1120 can be at least partially positioned within staplecavities, or voids, 1115 in the second layer 1112 and, when the secondlayer 1112 is compressed, the staple cavities 1115 can collapse and, asa result, allow the second layer 1112 to collapse around the staples1120. In various embodiments, the second layer 1112 can comprise coverportions 1116 which can extend over the staple cavities 1115 andenclose, or at least partially enclose, the staple cavities 1115. FIG.7B illustrates the cover portions 1116 being crushed downwardly into thestaple cavities 1115. In certain embodiments, the second layer 1112 cancomprise one or more weakened portions which can facilitate the collapseof the second layer 1112. In various embodiments, such weakened portionscan comprise score marks, perforations, and/or thin cross-sections, forexample, which can facilitate a controlled collapse of the cartridgebody 1110. In at least one embodiment, the first layer 1111 can compriseone or more weakened portions which can facilitate the penetration ofthe staple legs 1121 through the first layer 1111. In variousembodiments, such weakened portions can comprise score marks,perforations, and/or thin cross-sections, for example, which can bealigned, or at least substantially aligned, with the staple legs 1121.

When the anvil 1140 is in a partially closed, unfired position,referring again to FIG. 7A, the anvil 1140 can be positioned a distance1101 a away from the cartridge support surface 1131 such that a gap isdefined therebetween. This gap can be filled by the staple cartridge1100, having a staple cartridge height 1102 a, and the tissue T. As theanvil 1140 is moved downwardly to compress the staple cartridge 1100,referring again to FIG. 7B, the distance between the tissue contactingsurface 1141 and the cartridge support surface 1131 can be defined by adistance 1101 b which is shorter than the distance 1101 a. In variouscircumstances, the gap between the tissue-contacting surface 1141 ofanvil 1140 and the cartridge support surface 1131, defined by distance1101 b, may be larger than the original, undeformed staple cartridgeheight 1102 a. As the anvil 1140 is moved closer to the cartridgesupport surface 1131, referring now to FIG. 7C, the second layer 1112can continue to collapse and the distance between the staple legs 1121and the forming pockets 1142 can decrease. Similarly, the distancebetween the tissue-contacting surface 1141 and the cartridge supportsurface 1131 can decrease to a distance 1101 c which, in variousembodiments, may be greater than, equal to, or less than the original,undeformed cartridge height 1102 a. Referring now to FIG. 7D, the anvil1140 can be moved into a final, fired position in which the staples 1120have been fully formed, or at least formed to a desired height. In sucha position, the tissue-contacting surface 1141 of anvil 1140 can be adistance 1101 d away from the cartridge support surface 1131, whereinthe distance 1101 d can be shorter than the original, undeformedcartridge height 1102 a. As also illustrated in FIG. 7D, the staplecavities 1115 may be fully, or at least substantially, collapsed and thestaples 1120 may be completely, or at least substantially, surrounded bythe collapsed second layer 1112. In various circumstances, the anvil1140 can be thereafter moved away from the staple cartridge 1100. Oncethe anvil 1140 has been disengaged from the staple cartridge 1100, thecartridge body 1110 can at least partially re-expand in variouslocations, i.e., locations intermediate adjacent staples 1120, forexample. In at least one embodiment, the crushed cartridge body 1110 maynot resiliently re-expand. In various embodiments, the formed staples1120 and, in addition, the cartridge body 1110 positioned intermediateadjacent staples 1120 may apply pressure, or compressive forces, to thetissue T which may provide various therapeutic benefits.

As discussed above, referring again to the embodiment illustrated inFIG. 7A, each staple 1120 can comprise staple legs 1121 extendingtherefrom. Although staples 1120 are depicted as comprising two staplelegs 1121, various staples can be utilized which can comprise one stapleleg or, alternatively, more than two staple legs, such as three staplelegs or four staple legs, for example. As illustrated in FIG. 7A, eachstaple leg 1121 can be embedded in the second layer 1112 of thecartridge body 1110 such that the staples 1120 are secured within thesecond layer 1112. In various embodiments, the staples 1120 can beinserted into the staple cavities 1115 in cartridge body 1110 such thatthe tips 1123 of the staple legs 1121 enter into the cavities 1115before the bases 1122. After the tips 1123 have been inserted into thecavities 1115, in various embodiments, the tips 1123 can be pressed intothe cover portions 1116 and incise the second layer 1112. In variousembodiments, the staples 1120 can be seated to a sufficient depth withinthe second layer 1112 such that the staples 1120 do not move, or atleast substantially move, relative to the second layer 1112. In certainembodiments, the staples 1120 can be seated to a sufficient depth withinthe second layer 1112 such that the bases 1122 are positioned orembedded within the staple cavities 1115. In various other embodiments,the bases 1122 may not be positioned or embedded within the second layer1112. In certain embodiments, referring again to FIG. 7A, the bases 1122may extend below the bottom surface 1118 of the cartridge body 1110. Incertain embodiments, the bases 1122 can rest on, or can be directlypositioned against, the cartridge support surface 1130. In variousembodiments, the cartridge support surface 1130 can comprise supportfeatures extending therefrom and/or defined therein wherein, in at leastone such embodiment, the bases 1122 of the staples 1120 may bepositioned within and supported by one or more support grooves, slots,or troughs, 1132, for example, in the staple cartridge support 1130, asdescribed in greater detail further below.

In various embodiments, referring now to FIGS. 8 and 9, a staplecartridge, such as staple cartridge 1200, for example, can comprise acompressible, implantable cartridge body 1210 comprising an outer layer1211 and an inner layer 1212. Similar to the above, the staple cartridge1200 can comprise a plurality of staples 1220 positioned within thecartridge body 1210. In various embodiments, each staple 1220 cancomprise a base 1222 and one or more staple legs 1221 extendingtherefrom. In at least one such embodiment, the staple legs 1221 can beinserted into the inner layer 1212 and seated to a depth in which thebases 1222 of the staples 1220 abut and/or are positioned adjacent tothe bottom surface 1218 of the inner layer 1212, for example. In theembodiment depicted in FIGS. 8 and 9, the inner layer 1212 does notcomprise staple cavities configured to receive a portion of the staples1220 while, in other embodiments, the inner layer 1212 can comprise suchstaple cavities. In various embodiments, further to the above, the innerlayer 1212 can be comprised of a compressible material, such asbioabsorbable foam and/or oxidized regenerated cellulose (ORC), forexample, which can be configured to allow the cartridge body 1210 tocollapse when a compressive load is applied thereto. In variousembodiments, the inner layer 1212 can be comprised of a lyophilized foamcomprising polylactic acid (PLA) and/or polyglycolic acid (PGA), forexample. The ORC may be commercially available under the trade nameSurgicel and can comprise a loose woven fabric (like a surgical sponge),loose fibers (like a cotton ball), and/or a foam. In at least oneembodiment, the inner layer 1212 can be comprised of a materialincluding medicaments, such as freeze-dried thrombin and/or fibrin, forexample, contained therein and/or coated thereon which can bewater-activated and/or activated by fluids within the patient's body,for example. In at least one such embodiment, the freeze-dried thrombinand/or fibrin can be held on a Vicryl (PGA) matrix, for example. Incertain circumstances, however, the activatable medicaments can beunintentionally activated when the staple cartridge 1200 is insertedinto a surgical site within the patient, for example. In variousembodiments, referring again to FIGS. 8 and 9, the outer layer 1211 canbe comprised of a water impermeable, or at least substantially waterimpermeable, material such that liquids do not come into contact with,or at least substantially contact, the inner layer 1212 until after thecartridge body 1210 has been compressed and the staple legs havepenetrated the outer layer 1211 and/or after the outer layer 1211 hasbeen incised in some fashion. In various embodiments, the outer layer1211 can be comprised of a buttress material and/or plastic material,such as polydioxanone (PDS) and/or polyglycolic acid (PGA), for example.In certain embodiments, the outer layer 1211 can comprise a wrap whichsurrounds the inner layer 1212 and the staples 1220. More particularly,in at least one embodiment, the staples 1220 can be inserted into theinner layer 1212 and the outer layer 1211 can be wrapped around thesub-assembly comprising the inner layer 1212 and the staples 1220 andthen sealed.

In various embodiments described herein, the staples of a staplecartridge can be fully formed by an anvil when the anvil is moved into aclosed position. In various other embodiments, referring now to FIGS.10-13, the staples of a staple cartridge, such as staple cartridge 4100,for example, can be deformed by an anvil when the anvil is moved into aclosed position and, in addition, by a staple driver system which movesthe staples toward the closed anvil. The staple cartridge 4100 cancomprise a compressible cartridge body 4110 which can be comprised of afoam material, for example, and a plurality of staples 4120 at leastpartially positioned within the compressible cartridge body 4110. Invarious embodiments, the staple driver system can comprise a driverholder 4160, a plurality of staple drivers 4162 positioned within thedriver holder 4160, and a staple cartridge pan 4180 which can beconfigured to retain the staple drivers 4162 in the driver holder 4160.In at least one such embodiment, the staple drivers 4162 can bepositioned within one or more slots 4163 in the driver holder 4160wherein the sidewalls of the slots 4163 can assist in guiding the stapledrivers 4162 upwardly toward the anvil. In various embodiments, thestaples 4120 can be supported within the slots 4163 by the stapledrivers 4162 wherein, in at least one embodiment, the staples 4120 canbe entirely positioned in the slots 4163 when the staples 4120 and thestaple drivers 4162 are in their unfired positions. In certain otherembodiments, at least a portion of the staples 4120 can extend upwardlythrough the open ends 4161 of slots 4163 when the staples 4120 andstaple drivers 4162 are in their unfired positions. In at least one suchembodiment, referring primarily now to FIG. 11, the bases of the staples4120 can be positioned within the driver holder 4160 and the tips of thestaples 4120 can be embedded within the compressible cartridge body4110. In certain embodiments, approximately one-third of the height ofthe staples 4120 can be positioned within the driver holder 4160 andapproximately two-thirds of the height of the staples 4120 can bepositioned within the cartridge body 4110. In at least one embodiment,referring to FIG. 10A, the staple cartridge 4100 can further comprise awater impermeable wrap or membrane 4111 surrounding the cartridge body4110 and the driver holder 4160, for example.

In use, the staple cartridge 4100 can be positioned within a staplecartridge channel, for example, and the anvil can be moved toward thestaple cartridge 4100 into a closed position. In various embodiments,the anvil can contact and compress the compressible cartridge body 4110when the anvil is moved into its closed position. In certainembodiments, the anvil may not contact the staples 4120 when the anvilis in its closed position. In certain other embodiments, the anvil maycontact the legs of the staples 4120 and at least partially deform thestaples 4120 when the anvil is moved into its closed position. In eitherevent, the staple cartridge 4100 can further comprise one or more sleds4170 which can be advanced longitudinally within the staple cartridge4100 such that the sleds 4170 can sequentially engage the staple drivers4162 and move the staple drivers 4162 and the staples 4120 toward theanvil. In various embodiments, the sleds 4170 can slide between thestaple cartridge pan 4180 and the staple drivers 4162. In embodimentswhere the closure of the anvil has started the forming process of thestaples 4120, the upward movement of the staples 4120 toward the anvilcan complete the forming process and deform the staples 4120 to theirfully formed, or at least desired, height. In embodiments where theclosure of the anvil has not deformed the staples 4120, the upwardmovement of the staples 4120 toward the anvil can initiate and completethe forming process and deform the staples 4120 to their fully formed,or at least desired, height. In various embodiments, the sleds 4170 canbe advanced from a proximal end of the staple cartridge 4100 to a distalend of the staple cartridge 4100 such that the staples 4120 positionedin the proximal end of the staple cartridge 4100 are fully formed beforethe staples 4120 positioned in the distal end of the staple cartridge4100 are fully formed. In at least one embodiment, referring to FIG. 12,the sleds 4170 can each comprise at least one angled or inclined surface4711 which can be configured to slide underneath the staple drivers 4162and lift the staple drivers 4162 as illustrated in FIG. 13.

In various embodiments, further to the above, the staples 4120 can beformed in order to capture at least a portion of the tissue T and atleast a portion of the compressible cartridge body 4110 of the staplecartridge 4100 therein. After the staples 4120 have been formed, theanvil and the staple cartridge channel 4130 of the surgical stapler canbe moved away from the implanted staple cartridge 4100. In variouscircumstances, the cartridge pan 4180 can be fixedly engaged with thestaple cartridge channel 4130 wherein, as a result, the cartridge pan4180 can become detached from the compressible cartridge body 4110 asthe staple cartridge channel 4130 is pulled away from the implantedcartridge body 4110. In various embodiments, referring again to FIG. 10,the cartridge pan 4180 can comprise opposing side walls 4181 betweenwhich the cartridge body 4110 can be removably positioned. In at leastone such embodiment, the compressible cartridge body 4110 can becompressed between the side walls 4181 such that the cartridge body 4110can be removably retained therebetween during use and releasablydisengaged from the cartridge pan 4180 as the cartridge pan 4180 ispulled away. In at least one such embodiment, the driver holder 4160 canbe connected to the cartridge pan 4180 such that the driver holder 4160,the drivers 4162, and/or the sleds 4170 can remain in the cartridge pan4180 when the cartridge pan 4180 is removed from the surgical site. Incertain other embodiments, the drivers 4162 can be ejected from thedriver holder 4160 and left within the surgical site. In at least onesuch embodiment, the drivers 4162 can be comprised of a bioabsorbablematerial, such as polyglycolic acid (PGA) which is marketed under thetrade name Vicryl, polylactic acid (PLA or PLLA), polydioxanone (PDS),polyhydroxyalkanoate (PHA), poliglecaprone 25 (PGCL) which is marketedunder the trade name Monocryl, polycaprolactone (PCL), and/or acomposite of PGA, PLA, PDS, PHA, PGCL and/or PCL, for example. Invarious embodiments, the drivers 4162 can be attached to the staples4120 such that the drivers 4162 are deployed with the staples 4120. Inat least one such embodiment, each driver 4162 can comprise a troughconfigured to receive the bases of the staples 4120, for example,wherein, in at least one embodiment, the troughs can be configured toreceive the staple bases in a press-fit and/or snap-fit manner.

In certain embodiments, further to the above, the driver holder 4160and/or the sleds 4170 can be ejected from the cartridge pan 4180. In atleast one such embodiment, the sleds 4170 can slide between thecartridge pan 4180 and the driver holder 4160 such that, as the sleds4170 are advanced in order to drive the staple drivers 4162 and staples4120 upwardly, the sleds 4170 can move the driver holder 4160 upwardlyout of the cartridge pan 4180 as well. In at least one such embodiment,the driver holder 4160 and/or the sleds 4170 can be comprised of abioabsorbable material, such as polyglycolic acid (PGA) which ismarketed under the trade name Vicryl, polylactic acid (PLA or PLLA),polydioxanone (PDS), polyhydroxyalkanoate (PHA), poliglecaprone 25(PGCL) which is marketed under the trade name Monocryl, polycaprolactone(PCL), and/or a composite of PGA, PLA, PDS, PHA, PGCL and/or PCL, forexample. In various embodiments, the sleds 4170 can be integrally formedand/or attached to a drive bar, or cutting member, which pushes thesleds 4170 through the staple cartridge 4100. In such embodiments, thesleds 4170 may not be ejected from the cartridge pan 4180 and may remainwith the surgical stapler while, in other embodiments in which the sleds4170 are not attached to the drive bar, the sleds 4170 may be left inthe surgical site. In any event, further to the above, thecompressibility of the cartridge body 4110 can allow thicker staplecartridges to be used within an end effector of a surgical stapler asthe cartridge body 4110 can compress, or shrink, when the anvil of thestapler is closed. In certain embodiments, as a result of the staplesbeing at least partially deformed upon the closure of the anvil, tallerstaples, such as staples having an approximately 0.18″ staple height,for example, could be used, wherein approximately 0.12″ of the stapleheight can be positioned within the compressible layer 4110 and whereinthe compressible layer 4110 can have an uncompressed height ofapproximately 0.14″, for example.

In many embodiments described herein, a staple cartridge can comprise aplurality of staples therein. In various embodiments, such staples canbe comprised of a metal wire deformed into a substantially U-shapedconfiguration having two staple legs. Other embodiments are envisionedin which staples can comprise different configurations such as two ormore wires that have been joined together having three or more staplelegs. In various embodiments, the wire, or wires, used to form thestaples can comprise a round, or at least substantially round,cross-section. In at least one embodiment, the staple wires can compriseany other suitable cross-section, such as square and/or rectangularcross-sections, for example. In certain embodiments, the staples can becomprised of plastic wires. In at least one embodiment, the staples canbe comprised of plastic-coated metal wires. In various embodiments, acartridge can comprise any suitable type of fastener in addition to orin lieu of staples. In at least one such embodiment, such a fastener cancomprise pivotable arms which are folded when engaged by an anvil. Incertain embodiments, two-part fasteners could be utilized. In at leastone such embodiment, a staple cartridge can comprise a plurality offirst fastener portions and an anvil can comprise a plurality of secondfastener portions which are connected to the first fastener portionswhen the anvil is compressed against the staple cartridge. In certainembodiments, as described above, a sled or driver can be advanced withina staple cartridge in order to complete the forming process of thestaples. In certain embodiments, a sled or driver can be advanced withinan anvil in order to move one or more forming members downwardly intoengagement with the opposing staple cartridge and the staples, orfasteners, positioned therein.

In various embodiments described herein, a staple cartridge can comprisefour rows of staples stored therein. In at least one embodiment, thefour staple rows can be arranged in two inner staple rows and two outerstaple rows. In at least one such embodiment, an inner staple row and anouter staple row can be positioned on a first side of a cutting member,or knife, slot within the staple cartridge and, similarly, an innerstaple row and an outer staple row can be positioned on a second side ofthe cutting member, or knife, slot. In certain embodiments, a staplecartridge may not comprise a cutting member slot; however, such a staplecartridge may comprise a designated portion configured to be incised bya cutting member in lieu of a staple cartridge slot. In variousembodiments, the inner staple rows can be arranged within the staplecartridge such that they are equally, or at least substantially equally,spaced from the cutting member slot. Similarly, the outer staple rowscan be arranged within the staple cartridge such that they are equally,or at least substantially equally, spaced from the cutting member slot.In various embodiments, a staple cartridge can comprise more than orless than four rows of staples stored within a staple cartridge. In atleast one embodiment, a staple cartridge can comprise six rows ofstaples. In at least one such embodiment, the staple cartridge cancomprise three rows of staples on a first side of a cutting member slotand three rows of staples on a second side of the cutting member slot.In certain embodiments, a staple cartridge may comprise an odd number ofstaple rows. For example, a staple cartridge may comprise two rows ofstaples on a first side of a cutting member slot and three rows ofstaples on a second side of the cutting member slot. In variousembodiments, the staple rows can comprise staples having the same, or atleast substantially the same, unformed staple height. In certain otherembodiments, one or more of the staple rows can comprise staples havinga different unformed staple height than the other staples. In at leastone such embodiment, the staples on a first side of a cutting memberslot may have a first unformed height and the staples on a second sideof a cutting member slot may have a second unformed height which isdifferent than the first height, for example.

In various embodiments, as described above, a staple cartridge cancomprise a cartridge body including a plurality of staple cavitiesdefined therein. The cartridge body can comprise a deck and a top decksurface wherein each staple cavity can define an opening in the decksurface. As also described above, a staple can be positioned within eachstaple cavity such that the staples are stored within the cartridge bodyuntil they are ejected therefrom. Prior to being ejected from thecartridge body, in various embodiments, the staples can be containedwith the cartridge body such that the staples do not protrude above thedeck surface. As the staples are positioned below the deck surface, insuch embodiments, the possibility of the staples becoming damaged and/orprematurely contacting the targeted tissue can be reduced. In variouscircumstances, the staples can be moved between an unfired position inwhich they do not protrude from the cartridge body and a fired positionin which they have emerged from the cartridge body and can contact ananvil positioned opposite the staple cartridge. In various embodiments,the anvil, and/or the forming pockets defined within the anvil, can bepositioned a predetermined distance above the deck surface such that, asthe staples are being deployed from the cartridge body, the staples aredeformed to a predetermined formed height. In some circumstances, thethickness of the tissue captured between the anvil and the staplecartridge may vary and, as a result, thicker tissue may be capturedwithin certain staples while thinner tissue may be captured withincertain other staples. In either event, the clamping pressure, or force,applied to the tissue by the staples may vary from staple to staple orvary between a staple on one end of a staple row and a staple on theother end of the staple row, for example. In certain circumstances, thegap between the anvil and the staple cartridge deck can be controlledsuch that the staples apply a certain minimum clamping pressure withineach staple. In some such circumstances, however, significant variationof the clamping pressure within different staples may still exist.Surgical stapling instruments are disclosed in U.S. Pat. No. 7,380,696,which issued on Jun. 3, 2008, the entire disclosure of which isincorporated by reference herein. An illustrative multi-stroke handlefor the surgical stapling and severing instrument is described ingreater detail in the commonly-owned U.S. patent application entitledSURGICAL STAPLING INSTRUMENT INCORPORATING A MULTISTROKE FIRING POSITIONINDICATOR AND RETRACTION MECHANISM, Ser. No. 10/674,026, now U.S. Pat.No. 7,364,061, the disclosure of which is hereby incorporated byreference in its entirety. Other applications consistent with thepresent invention may incorporate a single firing stroke, such asdescribed in commonly owned U.S. patent application SURGICAL STAPLINGINSTRUMENT HAVING SEPARATE DISTINCT CLOSING AND FIRING SYSTEMS, Ser. No.10/441,632, now U.S. Pat. No. 7,000,818, the disclosure of which ishereby incorporated by reference in its entirety.

In various embodiments described herein, a staple cartridge can comprisemeans for compensating for the thickness of the tissue captured withinthe staples deployed from the staple cartridge. In various embodiments,referring to FIG. 14, a staple cartridge, such as staple cartridge10000, for example, can include a rigid first portion, such as supportportion 10010, for example, and a compressible second portion, such astissue thickness compensator 10020, for example. In at least oneembodiment, referring primarily to FIG. 16, the support portion 10010can comprise a cartridge body, a top deck surface 10011, and a pluralityof staple cavities 10012 wherein, similar to the above, each staplecavity 10012 can define an opening in the deck surface 10011. A staple10030, for example, can be removably positioned in each staple cavity10012. In at least one such embodiment, each staple 10030 can comprise abase 10031 and one or more legs 10032 extending from the base 10031.Prior to the staples 10030 being deployed, as also described in greaterdetail below, the bases 10031 of the staples 10030 can be supported bystaple drivers positioned within the support portion 10010 and,concurrently, the legs 10032 of the staples 10030 can be at leastpartially contained within the staple cavities 10012. In variousembodiments, the staples 10030 can be deployed between an unfiredposition and a fired position such that the legs 10032 move through thetissue thickness compensator 10020, penetrate through a top surface ofthe tissue thickness compensator 10020, penetrate the tissue T, andcontact an anvil positioned opposite the staple cartridge 10000. As thelegs 10032 are deformed against the anvil, the legs 10032 of each staple10030 can capture a portion of the tissue thickness compensator 10020and a portion of the tissue T within each staple 10030 and apply acompressive force to the tissue. Further to the above, the legs 10032 ofeach staple 10030 can be deformed downwardly toward the base 10031 ofthe staple to form a staple entrapment area 10039 in which the tissue Tand the tissue thickness compensator 10020 can be captured. In variouscircumstances, the staple entrapment area 10039 can be defined betweenthe inner surfaces of the deformed legs 10032 and the inner surface ofthe base 10031. The size of the entrapment area for a staple can dependon several factors such as the length of the legs, the diameter of thelegs, the width of the base, and/or the extent in which the legs aredeformed, for example.

In previous embodiments, a surgeon was often required to select theappropriate staples having the appropriate staple height for the tissuebeing stapled. For example, a surgeon could select tall staples for usewith thick tissue and short staples for use with thin tissue. In somecircumstances, however, the tissue being stapled did not have aconsistent thickness and, thus, some staples were unable to achieve thedesired fired configuration. For example, FIG. 48 illustrates a tallstaple used in thin tissue. Referring now to FIG. 49, when a tissuethickness compensator, such as tissue thickness compensator 10020, forexample, is used with thin tissue, for example, the larger staple may beformed to a desired fired configuration.

Owing to the compressibility of the tissue thickness compensator, thetissue thickness compensator can compensate for the thickness of thetissue captured within each staple. More particularly, referring now toFIGS. 43 and 44, a tissue thickness compensator, such as tissuethickness compensator 10020, for example, can consume larger and/orsmaller portions of the staple entrapment area 10039 of each staple10030 depending on the thickness and/or type of tissue contained withinthe staple entrapment area 10039. For example, if thinner tissue T iscaptured within a staple 10030, the tissue thickness compensator 10020can consume a larger portion of the staple entrapment area 10039 ascompared to circumstances where thicker tissue T is captured within thestaple 10030. Correspondingly, if thicker tissue T is captured within astaple 10030, the tissue thickness compensator 10020 can consume asmaller portion of the staple entrapment area 10039 as compared to thecircumstances where thinner tissue T is captured within the staple10030. In this way, the tissue thickness compensator can compensate forthinner tissue and/or thicker tissue and assure that a compressivepressure is applied to the tissue irrespective, or at leastsubstantially irrespective, of the tissue thickness captured within thestaples. In addition to the above, the tissue thickness compensator10020 can compensate for different types, or compressibilities, oftissues captured within different staples 10030. Referring now to FIG.44, the tissue thickness compensator 10020 can apply a compressive forceto vascular tissue T which can include vessels V and, as a result,restrict the flow of blood through the less compressible vessels V whilestill applying a desired compressive pressure to the surrounding tissueT. In various circumstances, further to the above, the tissue thicknesscompensator 10020 can also compensate for malformed staples. Referringto FIG. 45, the malformation of various staples 10030 can result inlarger staple entrapment areas 10039 being defined within such staples.Owing to the resiliency of the tissue thickness compensator 10020,referring now to FIG. 46, the tissue thickness compensator 10020positioned within malformed staples 10030 may still apply a sufficientcompressive pressure to the tissue T eventhough the staple entrapmentareas 10039 defined within such malformed staples 10030 may be enlarged.In various circumstances, the tissue thickness compensator 10020 locatedintermediate adjacent staples 10030 can be biased against the tissue Tby properly-formed staples 10030 surrounding a malformed staple 10030and, as a result, apply a compressive pressure to the tissue surroundingand/or captured within the malformed staple 10030, for example. Invarious circumstances, a tissue thickness compensator can compensate fordifferent tissue densities which can arise due to calcifications,fibrous areas, and/or tissue that has been previously stapled ortreated, for example.

In various embodiments, a fixed, or unchangeable, tissue gap can bedefined between the support portion and the anvil and, as a result, thestaples may be deformed to a predetermined height regardless of thethickness of the tissue captured within the staples. When a tissuethickness compensator is used with these embodiments, the tissuethickness compensator can adapt to the tissue captured between the anviland the support portion staple cartridge and, owing to the resiliency ofthe tissue thickness compensator, the tissue thickness compensator canapply an additional compressive pressure to the tissue. Referring now toFIGS. 50-55, a staple 10030 has been formed to a predefined height H.With regard to FIG. 50, a tissue thickness compensator has not beenutilized and the tissue T consumes the entirety of the staple entrapmentarea 10039. With regard to FIG. 57, a portion of a tissue thicknesscompensator 10020 has been captured within the staple 10030, compressedthe tissue T, and consumed at least a portion of the staple entrapmentarea 10039. Referring now to FIG. 52, thin tissue T has been capturedwithin the staple 10030. In this embodiment, the compressed tissue T hasa height of approximately 2/9H and the compressed tissue thicknesscompensator 10020 has a height of approximately 7/9H, for example.Referring now to FIG. 53, tissue T having an intermediate thickness hasbeen captured within the staple 10030. In this embodiment, thecompressed tissue T has a height of approximately 4/9H and thecompressed tissue thickness compensator 10020 has a height ofapproximately 5/9H, for example. Referring now to FIG. 54, tissue Thaving an intermediate thickness has been captured within the staple10030. In this embodiment, the compressed tissue T has a height ofapproximately 2/3H and the compressed tissue thickness compensator 10020has a height of approximately 1/3H, for example. Referring now to FIG.53, thick tissue T has been captured within the staple 10030. In thisembodiment, the compressed tissue T has a height of approximately 8/9Hand the compressed tissue thickness compensator 10020 has a height ofapproximately 1/9H, for example. In various circumstances, the tissuethickness compensator can comprise a compressed height which comprisesapproximately 10% of the staple entrapment height, approximately 20% ofthe staple entrapment height, approximately 30% of the staple entrapmentheight, approximately 40% of the staple entrapment height, approximately50% of the staple entrapment height, approximately 60% of the stapleentrapment height, approximately 70% of the staple entrapment height,approximately 80% of the staple entrapment height, and/or approximately90% of the staple entrapment height, for example.

In various embodiments, the staples 10030 can comprise any suitableunformed height. In certain embodiments, the staples 10030 can comprisean unformed height between approximately 2 mm and approximately 4.8 mm,for example. The staples 10030 can comprise an unformed height ofapproximately 2.0 mm, approximately 2.5 mm, approximately 3.0 mm,approximately 3.4 mm, approximately 3.5 mm, approximately 3.8 mm,approximately 4.0 mm, approximately 4.1 mm, and/or approximately 4.8 mm,for example. In various embodiments, the height H to which the staplescan be deformed can be dictated by the distance between the deck surface10011 of the support portion 10010 and the opposing anvil. In at leastone embodiment, the distance between the deck surface 10011 and thetissue-contacting surface of the anvil can be approximately 0.097″, forexample. The height H can also be dictated by the depth of the formingpockets defined within the anvil. In at least one embodiment, theforming pockets can have a depth measured from the tissue-contactingsurface, for example. In various embodiments, as described in greaterdetail below, the staple cartridge 10000 can further comprise stapledrivers which can lift the staples 10030 toward the anvil and, in atleast one embodiment, lift, or “overdrive”, the staples above the decksurface 10011. In such embodiments, the height H to which the staples10030 are formed can also be dictated by the distance in which thestaples 10030 are overdriven. In at least one such embodiment, thestaples 10030 can be overdriven by approximately 0.028″, for example,and can result in the staples 10030 being formed to a height ofapproximately 0.189″, for example. In various embodiments, the staples10030 can be formed to a height of approximately 0.8 mm, approximately1.0 mm, approximately 1.5 mm, approximately 1.8 mm, approximately 2.0mm, and/or approximately 2.25 mm, for example. In certain embodiments,the staples can be formed to a height between approximately 2.25 mm andapproximately 3.0 mm, for example. Further to the above, the height ofthe staple entrapment area of a staple can be determined by the formedheight of the staple and the width, or diameter, of the wire comprisingthe staple. In various embodiments, the height of the staple entrapmentarea 10039 of a staple 10030 can comprise the formed height H of thestaple less two diameter widths of the wire. In certain embodiments, thestaple wire can comprise a diameter of approximately 0.0089″, forexample. In various embodiments, the staple wire can comprise a diameterbetween approximately 0.0069″ and approximately 0.0119″, for example. Inat least one exemplary embodiment, the formed height H of a staple 10030can be approximately 0.189″ and the staple wire diameter can beapproximately 0.0089″ resulting in a staple entrapment height ofapproximately 0.171″, for example.

In various embodiments, further to the above, the tissue thicknesscompensator can comprise an uncompressed, or pre-deployed, height andcan be configured to deform to one of a plurality of compressed heights.In certain embodiments, the tissue thickness compensator can comprise anuncompressed height of approximately 0.125″, for example. In variousembodiments, the tissue thickness compensator can comprise anuncompressed height of greater than or equal to approximately 0.080″,for example. In at least one embodiment, the tissue thicknesscompensator can comprise an uncompressed, or pre-deployed, height whichis greater than the unfired height of the staples. In at least oneembodiment, the uncompressed, or pre-deployed, height of the tissuethickness compensator can be approximately 10% taller, approximately 20%taller, approximately 30% taller, approximately 40% taller,approximately 50% taller, approximately 60% taller, approximately 70%taller, approximately 80% taller, approximately 90% taller, and/orapproximately 100% taller than the unfired height of the staples, forexample. In at least one embodiment, the uncompressed, or pre-deployed,height of the tissue thickness compensator can be up to approximately100% taller than the unfired height of the staples, for example. Incertain embodiments, the uncompressed, or pre-deployed, height of thetissue thickness compensator can be over 100% taller than the unfiredheight of the staples, for example. In at least one embodiment, thetissue thickness compensator can comprise an uncompressed height whichis equal to the unfired height of the staples. In at least oneembodiment, the tissue thickness compensator can comprise anuncompressed height which is less than the unfired height of thestaples. In at least one embodiment, the uncompressed, or pre-deployed,height of the thickness compensator can be approximately 10% shorter,approximately 20% shorter, approximately 30% shorter, approximately 40%shorter, approximately 50% shorter, approximately 60% shorter,approximately 70% shorter, approximately 80% shorter, and/orapproximately 90% shorter than the unfired height of the staples, forexample. In various embodiments, the compressible second portion cancomprise an uncompressed height which is taller than an uncompressedheight of the tissue T being stapled. In certain embodiments, the tissuethickness compensator can comprise an uncompressed height which is equalto an uncompressed height of the tissue T being stapled. In variousembodiments, the tissue thickness compensator can comprise anuncompressed height which is shorter than an uncompressed height of thetissue T being stapled.

As described above, a tissue thickness compensator can be compressedwithin a plurality of formed staples regardless of whether thick tissueor thin tissue is captured within the staples. In at least one exemplaryembodiment, the staples within a staple line, or row, can be deformedsuch that the staple entrapment area of each staple comprises a heightof approximately 2.0 mm, for example, wherein the tissue T and thetissue thickness compensator can be compressed within this height. Incertain circumstances, the tissue T can comprise a compressed height ofapproximately 1.75 mm within the staple entrapment area while the tissuethickness compensator can comprise a compressed height of approximately0.25 mm within the staple entrapment area, thereby totaling theapproximately 2.0 mm staple entrapment area height, for example. Incertain circumstances, the tissue T can comprise a compressed height ofapproximately 1.50 mm within the staple entrapment area while the tissuethickness compensator can comprise a compressed height of approximately0.50 mm within the staple entrapment area, thereby totaling theapproximately 2.0 mm staple entrapment area height, for example. Incertain circumstances, the tissue T can comprise a compressed height ofapproximately 1.25 mm within the staple entrapment area while the tissuethickness compensator can comprise a compressed height of approximately0.75 mm within the staple entrapment area, thereby totaling theapproximately 2.0 mm staple entrapment area height, for example. Incertain circumstances, the tissue T can comprise a compressed height ofapproximately 1.0 mm within the staple entrapment area while the tissuethickness compensator can comprise a compressed height of approximately1.0 mm within the staple entrapment area, thereby totaling theapproximately 2.0 mm staple entrapment area height, for example. Incertain circumstances, the tissue T can comprise a compressed height ofapproximately 0.75 mm within the staple entrapment area while the tissuethickness compensator can comprise a compressed height of approximately1.25 mm within the staple entrapment area, thereby totaling theapproximately 2.0 mm staple entrapment area height, for example. Incertain circumstances, the tissue T can comprise a compressed height ofapproximately 1.50 mm within the staple entrapment area while the tissuethickness compensator can comprise a compressed height of approximately0.50 mm within the staple entrapment area, thereby totaling theapproximately 2.0 mm staple entrapment area height, for example. Incertain circumstances, the tissue T can comprise a compressed height ofapproximately 0.25 mm within the staple entrapment area while the tissuethickness compensator can comprise a compressed height of approximately1.75 mm within the staple entrapment area, thereby totaling theapproximately 2.0 mm staple entrapment area height, for example.

In various embodiments, further to the above, the tissue thicknesscompensator can comprise an uncompressed height which is less than thefired height of the staples. In certain embodiments, the tissuethickness compensator can comprise an uncompressed height which is equalto the fired height of the staples. In certain other embodiments, thetissue thickness compensator can comprise an uncompressed height whichis taller than the fired height of the staples. In at least one suchembodiment, the uncompressed height of a tissue thickness compensatorcan comprise a thickness which is approximately 110% of the formedstaple height, approximately 120% of the formed staple height,approximately 130% of the formed staple height, approximately 140% ofthe formed staple height, approximately 150% of the formed stapleheight, approximately 160% of the formed staple height, approximately170% of the formed staple height, approximately 180% of the formedstaple height, approximately 190% of the formed staple height, and/orapproximately 200% of the formed staple height, for example. In certainembodiments, the tissue thickness compensator can comprise anuncompressed height which is more than twice the fired height of thestaples. In various embodiments, the tissue thickness compensator cancomprise a compressed height which is from approximately 85% toapproximately 150% of the formed staple height, for example. In variousembodiments, as described above, the tissue thickness compensator can becompressed between an uncompressed thickness and a compressed thickness.In certain embodiments, the compressed thickness of a tissue thicknesscompensator can be approximately 10% of its uncompressed thickness,approximately 20% of its uncompressed thickness, approximately 30% ofits uncompressed thickness, approximately 40% of its uncompressedthickness, approximately 50% of its uncompressed thickness,approximately 60% of its uncompressed thickness, approximately 70% ofits uncompressed thickness, approximately 80% of its uncompressedthickness, and/or approximately 90% of its uncompressed thickness, forexample. In various embodiments, the uncompressed thickness of thetissue thickness compensator can be approximately two times,approximately ten times, approximately fifty times, and/or approximatelyone hundred times thicker than its compressed thickness, for example. Inat least one embodiment, the compressed thickness of the tissuethickness compensator can be between approximately 60% and approximately99% of its uncompressed thickness. In at least one embodiment, theuncompressed thickness of the tissue thickness compensator can be atleast 50% thicker than its compressed thickness. In at least oneembodiment, the uncompressed thickness of the tissue thicknesscompensator can be up to one hundred times thicker than its compressedthickness. In various embodiments, the compressible second portion canbe elastic, or at least partially elastic, and can bias the tissue Tagainst the deformed legs of the staples. In at least one suchembodiment, the compressible second portion can resiliently expandbetween the tissue T and the base of the staple in order to push thetissue T against the legs of the staple. In certain embodiments,discussed in further detail below, the tissue thickness compensator canbe positioned intermediate the tissue T and the deformed staple legs. Invarious circumstances, as a result of the above, the tissue thicknesscompensator can be configured to consume any gaps within the stapleentrapment area.

In various embodiments, the tissue thickness compensator may comprisematerials characterized by one or more of the following properties:biocompatible, bioabsorable, bioresorbable, biodurable, biodegradable,compressible, fluid absorbable, swellable, self-expandable, bioactive,medicament, pharmaceutically active, anti-adhesion, haemostatic,antibiotic, anti-microbial, anti-viral, nutritional, adhesive,permeable, hydrophilic and/or hydrophobic, for example. In variousembodiments, a surgical instrument comprising an anvil and a staplecartridge may comprise a tissue thickness compensator associated withthe anvil and/or staple cartridge comprising at least one of ahaemostatic agent, such as fibrin and thrombin, an antibiotic, such asdoxycpl, and medicament, such as matrix metalloproteinases (MMPs).

In various embodiments, the tissue thickness compensator may comprisesynthetic and/or non-synthetic materials. The tissue thicknesscompensator may comprise a polymeric composition comprising one or moresynthetic polymers and/or one or more non-synthetic polymers. Thesynthetic polymer may comprise a synthetic absorbable polymer and/or asynthetic non-absorbable polymer. In various embodiments, the polymericcomposition may comprise a biocompatible foam, for example. Thebiocompatible foam may comprise a porous, open cell foam and/or aporous, closed cell foam, for example. The biocompatible foam may have auniform pore morphology or may have a gradient pore morphology (i.e.small pores gradually increasing in size to large pores across thethickness of the foam in one direction). In various embodiments, thepolymeric composition may comprise one or more of a porous scaffold, aporous matrix, a gel matrix, a hydrogel matrix, a solution matrix, afilamentous matrix, a tubular matrix, a composite matrix, a membranousmatrix, a biostable polymer, and a biodegradable polymer, andcombinations thereof. For example, the tissue thickness compensator maycomprise a foam reinforced by a filamentous matrix or may comprise afoam having an additional hydrogel layer that expands in the presence ofbodily fluids to further provide the compression on the tissue. Invarious embodiments, a tissue thickness compensator could also becomprised of a coating on a material and/or a second or third layer thatexpands in the presence of bodily fluids to further provide thecompression on the tissue. Such a layer could be a hydrogel that couldbe a synthetic and/or naturally derived material and could be eitherbiodurable and/or biodegradable, for example. In various embodiments,the tissue thickness compensator may comprise a microgel or a nanogel.The hydrogel may comprise carbohydrate-derived microgels and/ornanogels. In certain embodiments, a tissue thickness compensator may bereinforced with fibrous non-woven materials or fibrous mesh typeelements, for example, that can provide additional flexibility,stiffness, and/or strength. In various embodiments, a tissue thicknesscompensator that has a porous morphology which exhibits a gradientstructure such as, for example, small pores on one surface and largerpores on the other surface. Such morphology could be more optimal fortissue in-growth or haemostatic behavior. Further, the gradient could bealso compositional with a varying bio-absorption profile. A short termabsorption profile may be preferred to address hemostasis while a longterm absorption profile may address better tissue healing withoutleakages.

Examples of non-synthetic materials include, but are not limited to,lyophilized polysaccharide, glycoprotein, bovine pericardium, collagen,gelatin, fibrin, fibrinogen, elastin, proteoglycan, keratin, albumin,hydroxyethyl cellulose, cellulose, oxidized cellulose, oxidizedregenerated cellulose (ORC), hydroxypropyl cellulose, carboxyethylcellulose, carboxymethylcellulose, chitan, chitosan, casein, alginate,and combinations thereof.

Examples of synthetic absorbable materials include, but are not limitedto, poly(lactic acid) (PLA), poly(L-lactic acid) (PLLA),polycaprolactone (PCL), polyglycolic acid (PGA), poly(trimethylenecarbonate) (TMC), polyethylene terephthalate (PET), polyhydroxyalkanoate(PHA), a copolymer of glycolide and ε-caprolactone (PGCL), a copolymerof glycolide and -trimethylene carbonate, poly(glycerol sebacate) (PGS),poly(dioxanone) (PDS), polyesters, poly(orthoesters), polyoxaesters,polyetheresters, polycarbonates, polyamide esters, polyanhydrides,polysaccharides, poly(ester-amides), tyrosine-based polyarylates,polyamines, tyrosine-based polyiminocarbonates, tyrosine-basedpolycarbonates, poly(D,L-lactide-urethane), poly(hydroxybutyrate),poly(B-hydroxybutyrate), poly(E-caprolactone), polyethyleneglycol (PEG),poly[bis(carboxylatophenoxy) phosphazene] poly(amino acids),pseudo-poly(amino acids), absorbable polyurethanes, poly (phosphazine),polyphosphazenes, polyalkyleneoxides, polyacrylamides,polyhydroxyethylmethylacrylate, polyvinylpyrrolidone, polyvinylalcohols, poly(caprolactone), polyacrylic acid, polyacetate,polypropylene, aliphatic polyesters, glycerols, copoly(ether-esters),polyalkylene oxalates, polyamides, poly(iminocarbonates), polyalkyleneoxalates, and combinations thereof. In various embodiments, thepolyester is may be selected from the group consisting of polylactides,polyglycolides, trimethylene carbonates, polydioxanones,polycaprolactones, polybutesters, and combinations thereof.

In various embodiments, the synthetic absorbable polymer may compriseone or more of 90/10 poly(glycolide-L-lactide) copolymer, commerciallyavailable from Ethicon, Inc. under the trade designation VICRYL(polyglactic 910), polyglycolide, commercially available from AmericanCyanamid Co. under the trade designation DEXON, polydioxanone,commercially available from Ethicon, Inc. under the trade designationPDS, poly(glycolide-trimethylene carbonate) random block copolymer,commercially available from American Cyanamid Co. under the tradedesignation MAXON, 75/25poly(glycolide-□-caprolactone-poliglecaprolactone 25) copolymer,commercially available from Ethicon under the trade designationMONOCRYL, for example.

Examples of synthetic non-absorbable materials include, but are notlimited to, polyurethane, polypropylene (PP), polyethylene (PE),polycarbonate, polyamides, such as nylon, polyvinylchloride (PVC),polymethylmetacrylate (PMMA), polystyrene (PS), polyester,polyetheretherketone (PEEK), polytetrafluoroethylene (PTFE),polytrifluorochloroethylene (PTFCE), polyvinylfluoride (PVF),fluorinated ethylene propylene (FEP), polyacetal, polysulfone, silicons,and combinations thereof. The synthetic non-absorbable polymers mayinclude, but are not limited to, foamed elastomers and porouselastomers, such as, for example, silicone, polyisoprene, and rubber. Invarious embodiments, the synthetic polymers may comprise expandedpolytetrafluoroethylene (ePTFE), commercially available from W. L. Gore& Associates, Inc. under the trade designation GORE-TEX Soft TissuePatch and co-polyetherester urethane foam commercially available fromPolyganics under the trade designation NASOPORE.

In various embodiments, the polymeric composition may comprise fromapproximately 50% to approximately 90% by weight of the polymericcomposition of PLLA and approximately 50% to approximately 10% by weightof the polymeric composition of PCL, for example. In at least oneembodiment, the polymeric composition may comprise approximately 70% byweight of PLLA and approximately 30% by weight of PCL, for example. Invarious embodiments, the polymeric composition may comprise fromapproximately 55% to approximately 85% by weight of the polymericcomposition of PGA and 15% to 45% by weight of the polymeric compositionof PCL, for example. In at least one embodiment, the polymericcomposition may comprise approximately 65% by weight of PGA andapproximately 35% by weight of PCL, for example. In various embodiments,the polymeric composition may comprise from approximately 90% toapproximately 95% by weight of the polymeric composition of PGA andapproximately 5% to approximately 10% by weight of the polymericcomposition of PLA, for example.

In various embodiments, the synthetic absorbable polymer may comprise abioabsorbable, biocompatible elastomeric copolymer. Suitablebioabsorbable, biocompatible elastomeric copolymers include but are notlimited to copolymers of □-caprolactone and glycolide (preferably havinga mole ratio of □-caprolactone to glycolide of from about 30:70 to about70:30, preferably 35:65 to about 65:35, and more preferably 45:55 to35:65); elastomeric copolymers of □-caprolactone and lactide, includingL-lactide, D-lactide blends thereof or lactic acid copolymers(preferably having a mole ratio of □-caprolactone to lactide of fromabout 35:65 to about 65:35 and more preferably 45:55 to 30:70)elastomeric copolymers of p-dioxanone (1,4-dioxan-2-one) and lactideincluding L-lactide, D-lactide and lactic acid (preferably having a moleratio of p-dioxanone to lactide of from about 40:60 to about 60:40);elastomeric copolymers of □-caprolactone and p-dioxanone (preferablyhaving a mole ratio of □-caprolactone to p-dioxanone of from about 30:70to about 70:30); elastomeric copolymers of p-dioxanone and trimethylenecarbonate (preferably having a mole ratio of p-dioxanone to trimethylenecarbonate of from about 30:70 to about 70:30); elastomeric copolymers oftrimethylene carbonate and glycolide (preferably having a mole ratio oftrimethylene carbonate to glycolide of from about 30:70 to about 70:30);elastomeric copolymer of trimethylene carbonate and lactide includingL-lactide, D-lactide, blends thereof or lactic acid copolymers(preferably having a mole ratio of trimethylene carbonate to lactide offrom about 30:70 to about 70:30) and blends thereof. In one embodiment,the elastomeric copolymer is a copolymer of glycolide and□-caprolactone. In another embodiment, the elastomeric copolymer is acopolymer of lactide and □-caprolactone.

The disclosures of U.S. Pat. No. 5,468,253, entitled ELASTOMERIC MEDICALDEVICE, which issued on Nov. 21, 1995, and U.S. Pat. No. 6,325,810,entitled FOAM BUTTRESS FOR STAPLING APPARATUS, which issued on Dec. 4,2001, are hereby incorporated by reference in their respectiveentireties.

In various embodiments, the tissue thickness compensator may comprise anemulsifier. Examples of emulsifiers may include, but are not limited to,water-soluble polymers, such as, polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), polyethylene glycol (PEG), polypropylene glycol(PPG), PLURONICS, TWEENS, polysaccharides and combinations thereof.

In various embodiments, the tissue thickness compensator may comprise asurfactant. Examples of surfactants may include, but are not limited to,polyacrylic acid, methalose, methyl cellulose, ethyl cellulose, propylcellulose, hydroxy ethyl cellulose, carboxy methyl cellulose,polyoxyethylene cetyl ether, polyoxyethylene lauryl ether,polyoxyethylene octyl ether, polyoxyethylene octylphenyl ether,polyoxyethylene oleyl ether, polyoxyethylene sorbitan monolaurate,polyoxyethylene stearyl ether, polyoxyethylene nonylphenyl ether,dialkylphenoxy poly(ethyleneoxy) ethanol, and polyoxamers.

In various embodiments, the polymeric composition may comprise apharmaceutically active agent. The polymeric composition may release atherapeutically effective amount of the pharmaceutically active agent.In various embodiments, the pharmaceutically active agent may bereleased as the polymeric composition is desorbed/absorbed. In variousembodiments, the pharmaceutically active agent may be released intofluid, such as, for example, blood, passing over or through thepolymeric composition. Examples of pharmaceutically active agents mayinclude, but are not limited to, haemostatic agents and drugs, such as,for example, fibrin, thrombin, and oxidized regenerated cellulose (ORC);anti-inflammatory drugs, such as, for example, diclofenac, aspirin,naproxen, sulindac, and hydrocortisone; antibiotic and antimicrobialdrug or agents, such as, for example, triclosan, ionic silver,ampicillin, gentamicin, polymyxin B, chloramphenicol; and anticanceragents, such as, for example, cisplatin, mitomycin, adriamycin.

In various embodiments, the polymeric composition may comprise ahaemostatic material. The tissue thickness compensator may comprisehaemostatic materials comprising poly(lactic acid), poly(glycolic acid),poly(hydroxybutyrate), poly(caprolactone), poly(dioxanone),polyalkyleneoxides, copoly(ether-esters), collagen, gelatin, thrombin,fibrin, fibrinogen, fibronectin, elastin, albumin, hemoglobin,ovalbumin, polysaccharides, hyaluronic acid, chondroitin sulfate,hydroxyethyl starch, hydroxyethyl cellulose, cellulose, oxidizedcellulose, hydroxypropyl cellulose, carboxyethyl cellulose,carboxymethyl cellulose, chitan, chitosan, agarose, maltose,maltodextrin, alginate, clotting factors, methacrylate, polyurethanes,cyanoacrylates, platelet agonists, vasoconstrictors, alum, calcium, RGDpeptides, proteins, protamine sulfate, F-amino caproic acid, ferricsulfate, ferric subsulfates, ferric chloride, zinc, zinc chloride,aluminum chloride, aluminum sulfates, aluminum acetates, permanganates,tannins, bone wax, polyethylene glycols, fucans and combinationsthereof. The tissue thickness compensator may be characterized byhaemostatic properties.

The polymeric composition of a tissue thickness compensator may becharacterized by percent porosity, pore size, and/or hardness, forexample. In various embodiments, the polymeric composition may have apercent porosity from approximately 30% by volume to approximately 99%by volume, for example. In certain embodiments, the polymericcomposition may have a percent porosity from approximately 60% by volumeto approximately 98% by volume, for example. In various embodiments, thepolymeric composition may have a percent porosity from approximately 85%by volume to approximately 97% by volume, for example. In at least oneembodiment, the polymeric composition may comprise approximately 70% byweight of PLLA and approximately 30% by weight of PCL, for example, andcan comprise approximately 90% porosity by volume, for example. In atleast one such embodiment, as a result, the polymeric composition wouldcomprise approximately 10% copolymer by volume. In at least oneembodiment, the polymeric composition may comprise approximately 65% byweight of PGA and approximately 35% by weight of PCL, for example, andcan have a percent porosity from approximately 93% by volume toapproximately 95% by volume, for example. In various embodiments, thepolymeric composition may comprise greater than 85% porosity by volume.The polymeric composition may have a pore size from approximately 5micrometers to approximately 2000 micrometers, for example. In variousembodiments, the polymeric composition may have a pore size betweenapproximately 10 micrometers to approximately 100 micrometers, forexample. In at least one such embodiment, the polymeric composition cancomprise a copolymer of PGA and PCL, for example. In certainembodiments, the polymeric composition may have a pore size betweenapproximately 100 micrometers to approximately 1000 micrometers, forexample. In at least one such embodiment, the polymeric composition cancomprise a copolymer of PLLA and PCL, for example.

According to certain aspects, the hardness of a polymeric compositionmay be expressed in terms of the Shore Hardness, which can defined asthe resistance to permanent indentation of a material as determined witha durometer, such as a Shore Durometer. In order to assess the durometervalue for a given material, a pressure is applied to the material with adurometer indenter foot in accordance with ASTM procedure D2240-00,entitled, “Standard Test Method for Rubber Property-Durometer Hardness”,the entirety of which is incorporated herein by reference. The durometerindenter foot may be applied to the material for a sufficient period oftime, such as 15 seconds, for example, wherein a reading is then takenfrom the appropriate scale. Depending on the type of scale being used, areading of 0 can be obtained when the indenter foot completelypenetrates the material, and a reading of 100 can be obtained when nopenetration into the material occurs. This reading is dimensionless. Invarious embodiments, the durometer may be determined in accordance withany suitable scale, such as Type A and/or Type OO scales, for example,in accordance with ASTM D2240-00. In various embodiments, the polymericcomposition of a tissue thickness compensator may have a Shore Ahardness value from approximately 4 A to approximately 16 A, forexample, which is approximately 45 OO to approximately 65 OO on theShore OO range. In at least one such embodiment, the polymericcomposition can comprise a PLLA/PCL copolymer or a PGA/PCL copolymer,for example. In various embodiments, the polymeric composition of atissue thickness compensator may have a Shore A Hardness value of lessthan 15 A. In various embodiments, the polymeric composition of a tissuethickness compensator may have a Shore A Hardness value of less than 10A. In various embodiments, the polymeric composition of a tissuethickness compensator may have a Shore A Hardness value of less than 5A. In certain embodiments, the polymeric material may have a Shore OOcomposition value from approximately 35 OO to approximately 75 OO, forexample.

In various embodiments, the polymeric composition may have at least twoof the above-identified properties. In various embodiments, thepolymeric composition may have at least three of the above-identifiedproperties. The polymeric composition may have a porosity from 85% to97% by volume, a pore size from 5 micrometers to 2000 micrometers, and aShore A hardness value from 4 A to 16 A and Shore OO hardness value from45 OO to 65 OO, for example. In at least one embodiment, the polymericcomposition may comprise 70% by weight of the polymeric composition ofPLLA and 30% by weight of the polymeric composition of PCL having aporosity of 90% by volume, a pore size from 100 micrometers to 1000micrometers, and a Shore A hardness value from 4 A to 16 A and Shore OOhardness value from 45 OO to 65 OO, for example. In at least oneembodiment, the polymeric composition may comprise 65% by weight of thepolymeric composition of PGA and 35% by weight of the polymericcomposition of PCL having a porosity from 93% to 95% by volume, a poresize from 10 micrometers to 100 micrometers, and a Shore A hardnessvalue from 4 A to 16 A and Shore OO hardness value from 45 OO to 65 OO,for example.

In various embodiments, the tissue thickness compensator may comprise amaterial that expands. As discussed above, the tissue thicknesscompensator may comprise a compressed material that expands whenuncompressed or deployed, for example. In various embodiments, thetissue thickness compensator may comprise a self-expanding materialformed in situ. In various embodiments, the tissue thickness compensatormay comprise at least one precursor selected to spontaneously crosslinkwhen contacted with at least one of other precursor(s), water, and/orbodily fluids. In various embodiments, a first precursor may contact oneor more other precursors to form an expandable and/or swellable tissuethickness compensator. In various embodiments, the tissue thicknesscompensator may comprise a fluid-swellable composition, such as awater-swellable composition, for example. In various embodiments, thetissue thickness compensator may comprise a gel comprising water.

In various embodiments, the tissue thickness compensator may comprise abiodegradable foam having an encapsulation comprising dry hydrogelparticles or granules embedded therein. Without wishing to be bound toany particular theory, the encapsulations in the foam may be formed bycontacting an aqueous solution of a hydrogel precursor and an organicsolution of biocompatible materials to form the foam. In variousembodiments, the aqueous solution and organic solution may formmicelles. The aqueous solution and organic solution may be dried toencapsulate dry hydrogel particles or granules within the foam. Forexample, a hydrogel precursor, such as a hydrophilic polymer, may bedissolved in water to form a dispersion of micelles. The aqueoussolution may contact an organic solution of dioxane comprisingpoly(glycolic acid) and polycaprolactone. The aqueous and organicsolutions may be lyophilized to form a biodegradable foam having dryhydrogel particles or granules dispersed therein. Without wishing to bebound to any particular theory, it is believed that the micelles formthe encapsulation having the dry hydrogel particles or granulesdispersed within the foam structure. In certain embodiments, theencapsulation may be ruptured, and the dry hydrogel particles orgranules may contact a fluid, such as a bodily fluid, and expand.

In various embodiments, as described above, the tissue thicknesscompensator may comprise an initial thickness and an expanded thickness.In certain embodiments, the initial thickness of a tissue thicknesscompensator can be approximately 0.001% of its expanded thickness,approximately 0.01% of its expanded thickness, approximately 0.1% of itsexpanded thickness, approximately 1% of its expanded thickness,approximately 10% of its expanded thickness, approximately 20% of itsexpanded thickness, approximately 30% of its expanded thickness,approximately 40% of its expanded thickness, approximately 50% of itsexpanded thickness, approximately 60% of its expanded thickness,approximately 70% of its expanded thickness, approximately 80% of itsexpanded thickness, and/or approximately 90% of its expanded thickness,for example. In various embodiments, the expanded thickness of thetissue thickness compensator can be approximately two times,approximately five times, approximately ten times, approximately fiftytimes, approximately one hundred times, approximately two hundred times,approximately three hundred times, approximately four hundred times,approximately five hundred times, approximately six hundred times,approximately seven hundred times, approximately eight hundred times,approximately nine hundred times, and/or approximately one thousandtimes thicker than its initial thickness, for example. In variousembodiments, the initial thickness of the tissue thickness compensatorcan be up to 1% its expanded thickness, up to 5% its expanded thickness,up to 10% its expanded thickness, and up to 50% its expanded thickness.In various embodiments, the expanded thickness of the tissue thicknesscompensator can be at least 50% thicker than its initial thickness, atleast 100% thicker than its initial thickness, at least 300% thickerthan its initial thickness, and at least 500% thicker than its initialthickness. As described above, in various circumstances, as a result ofthe above, the tissue thickness compensator can be configured to consumeany gaps within the staple entrapment area.

As discussed above, in various embodiments, the tissue thicknesscompensator may comprise a hydrogel. In various embodiments, thehydrogel may comprise homopolymer hydrogels, copolymer hydrogels,multipolymer hydrogels, interpenetrating polymer hydrogels, andcombinations thereof. In various embodiments, the hydrogel may comprisemicrogels, nanogels, and combinations thereof. The hydrogel maygenerally comprise a hydrophilic polymer network capable of absorbingand/or retaining fluids. In various embodiments, the hydrogel maycomprise a non-crosslinked hydrogel, a crosslinked hydrogel, andcombinations thereof. The hydrogel may comprise chemical crosslinks,physical crosslinks, hydrophobic segments and/or water insolublesegments. The hydrogel may be chemically crosslinked by polymerization,small-molecule crosslinking, and/or polymer-polymer crosslinking. Thehydrogel may be physically crosslinked by ionic interactions,hydrophobic interactions, hydrogen bonding interactions,sterocomplexation, and/or supramolecular chemistry. The hydrogel may besubstantially insoluble due to the crosslinks, hydrophobic segmentsand/or water insoluble segments, but be expandable and/or swellable dueto absorbing and/or retaining fluids. In certain embodiments, theprecursor may crosslink with endogenous materials and/or tissues.

In various embodiments, the hydrogel may comprise an environmentallysensitive hydrogel (ESH). The ESH may comprise materials havingfluid-swelling properties that relate to environmental conditions. Theenvironmental conditions may include, but are not limited to, thephysical conditions, biological conditions, and/or chemical conditionsat the surgical site. In various embodiments, the hydrogel may swell orshrink in response to temperature, pH, electric fields, ionic strength,enzymatic and/or chemical reactions, electrical and/or magnetic stimuli,and other physiological and environmental variables, for example. Invarious embodiments, the ESH may comprise multifunctional acrylates,hydroxyethylmethacrylate (HEMA), elastomeric acrylates, and relatedmonomers.

In various embodiments, the tissue thickness compensator comprising ahydrogel may comprise at least one of the non-synthetic materials andsynthetic materials described above. The hydrogel may comprise asynthetic hydrogel and/or a non-synthetic hydrogel. In variousembodiments, the tissue thickness compensator may comprise a pluralityof layers. The plurality of the layers may comprise porous layers and/ornon-porous layers. For example, the tissue thickness compensator maycomprise a non-porous layer and a porous layer. In another example, thetissue thickness compensator may comprise a porous layer intermediate afirst non-porous layer and a second non-porous layer. In anotherexample, the tissue thickness compensator may comprise a non-porouslayer intermediate a first porous layer and a second porous layer. Thenon-porous layers and porous layers may be positioned in any orderrelative to the surfaces of the staple cartridge and/or anvil.

Examples of the non-synthetic material may include, but are not limitedto, albumin, alginate, carbohydrate, casein, cellulose, chitin,chitosan, collagen, blood, dextran, elastin, fibrin, fibrinogen,gelatin, heparin, hyaluronic acid, keratin, protein, serum, and starch.The cellulose may comprise hydroxyethyl cellulose, oxidized cellulose,oxidized regenerated cellulose (ORC), hydroxypropyl cellulose,carboxyethyl cellulose, carboxymethylcellulose, and combinationsthereof. The collagen may comprise bovine pericardium. The carbohydratemay comprise a polysaccharide, such as lyophilized polysaccharide. Theprotein may comprise glycoprotein, proteoglycan, and combinationsthereof.

Examples of the synthetic material may include, but are not limited to,poly(lactic acid), poly(glycolic acid), poly(hydroxybutyrate),poly(phosphazine), polyesters, polyethylene glycols, polyethylene oxide,polyethylene oxide-co-polypropylene oxide, co-polyethylene oxide,polyalkyleneoxides, polyacrylamides, polyhydroxyethylmethylacrylate,poly(vinylpyrrolidone), polyvinyl alcohols, poly(caprolactone),poly(dioxanone), polyacrylic acid, polyacetate, polypropylene, aliphaticpolyesters, glycerols, poly(amino acids), copoly(ether-esters),polyalkylene oxalates, polyamides, poly(iminocarbonates), polyoxaesters,polyorthoesters, polyphosphazenes and combinations thereof. In certainembodiments, the above non-synthetic materials may be syntheticallyprepared, e.g., synthetic hyaluronic acid, utilizing conventionalmethods.

In various embodiments, the hydrogel may be made from one or morehydrogel precursors. The precursor may comprise a monomer and/or amacromer. The hydrogel precursor may comprise an electrophile functionalgroup and/or a nucleophile electrophile functional group. In general,electrophiles may react with nucleophiles to form a bond. The term“functional group” as used herein refers to electrophilic ornucleophilic groups capable of reacting with each other to form a bond.Examples of electrophilic functional groups may include, but are notlimited to, N-hydroxysuccinimides (“NHS”), sulfosuccinimides,carbonyldiimidazole, sulfonyl chloride, aryl halides, sulfosuccinimidylesters, N-hydroxysuccinimidyl esters, succinimidyl esters such assuccinimidyl succinates and/or succinimidyl propionates, isocyanates,thiocyanates, carbodiimides, benzotriazole carbonates, epoxides,aldehydes, maleimides, imidoesters, combinations thereof, and the like.In at least one embodiment, the electrophilic functional group maycomprise a succinimidyl ester. Examples of nucleophile functional groupsmay include, but are not limited to, —NH₂, —SH, —OH, —PH₂, and—CO—NH—NH₂.

In various embodiments, the hydrogel may be formed from a singleprecursor or multiple precursors. In certain embodiments, the hydrogelmay be formed from a first precursor and a second precursor. The firsthydrogel precursor and second hydrogel precursor may form a hydrogel insitu and/or in vivo upon contact. The hydrogel precursor may generallyrefer to a polymer, functional group, macromolecule, small molecule,and/or crosslinker that can take part in a reaction to form a hydrogel.The precursor may comprise a homogeneous solution, heterogeneous, orphase separated solution in a suitable solvent, such as water or abuffer, for example. The buffer may have a pH from about 8 to about 12,such as, about 8.2 to about 9, for example. Examples of buffers mayinclude, but are not limited to borate buffers. In certain embodiments,the precursor(s) may be in an emulsion. In various embodiments, a firstprecursor may react with a second precursor to form a hydrogel. Invarious embodiments, the first precursor may spontaneously crosslinkwhen contacted with the second precursor. In various embodiments, afirst set of electrophilic functional groups on a first precursor mayreact with a second set of nucleophilic functional groups on a secondprecursor. When the precursors are mixed in an environment that permitsreaction (e.g., as relating to pH, temperature, and/or solvent), thefunctional groups may react with each other to form covalent bonds. Theprecursors may become crosslinked when at least some of the precursorsreact with more than one other precursor.

In various embodiments, the tissue thickness compensator may comprise atleast one monomer selected from the group consisting of 3-sulfopropylacrylate potassium salt (“KSPA”), sodium acrylate (“NaA”),N-(tris(hydroxylmethyl)methyl)acrylamide (“tris acryl”), and2-acrylamido-2-methyl-1-propane sulfonic acid (AMPS). The tissuethickness compensator may comprise a copolymer comprising two or moremonomers selected from the group consisting of KSPA, NaA, tris acryl,AMPS. The tissue thickness compensator may comprise homopolymers derivedfrom KSPA, NaA, trisacryl and AMPS. The tissue thickness compensator maycomprise hydrophilicity modifying monomers copolymerizable therewith.The hydrophilicity modifying monomers may comprise methylmethacrylate,butylacrylate, cyclohexylacrylate, styrene, styrene sulphonic acid.

In various embodiments, the tissue thickness compensator may comprise acrosslinker. The crosslinker may comprise a low molecular weight di- orpolyvinylic crosslinking agent, such as ethylenglycol diacrylate ordimethacrylate, di-, tri- or tetraethylen-glycol diacrylate ordimethacrylate, allyl (meth)acrylate, a C₂-C₈-alkylene diacrylate ordimethacrylate, divinyl ether, divinyl sulfone, di- and trivinylbenzene,trimethylolpropane triacrylate or trimethacrylate, pentaerythritoltetraacrylate or tetramethacrylate, bisphenol A diacrylate ordimethacrylate, methylene bisacrylamide or bismethacrylamide, ethylenebisacrylamide or ethylene bismethacrylamide, triallyl phthalate ordiallyl phthalate. In at least one embodiment, the crosslinker maycomprise N,N′-methylenebisacrylamide (“MBAA”).

In various embodiments, the tissue thickness compensator may comprise atleast one of acrylate and/or methacrylate functional hydrogels,biocompatible photoinitiator, alkyl-cyanoacrylates, isocyanatefunctional macromers, optionally comprising amine functional macromers,succinimidyl ester functional macromers, optionally comprising amineand/or sulfhydryl functional macromers, epoxy functional macromers,optionally comprising amine functional macromers, mixtures of proteinsand/or polypeptides and aldehyde crosslinkers, Genipin, andwater-soluble carbodiimides, anionic polysaccharides and polyvalentcations.

In various embodiments, the tissue thickness compensator may compriseunsaturated organic acid monomers, acrylic substituted alcohols, and/oracrylamides. In various embodiments, the tissue thickness compensatormay comprise methacrylic acids, acrylic acids, glycerolacrylate,glycerolmethacryulate, 2-hydroxyethylmethacrylate,2-hydroxyethylacrylate, 2-(dimethylaminoethyl) methacrylate, N-vinylpyrrolidone, methacrylamide, and/or N, N-dimethylacrylamidepoly(methacrylic acid).

In various embodiments, the tissue thickness compensator may comprise areinforcement material. In various embodiments, the reinforcementmaterial may comprise at least one of the non-synthetic materials andsynthetic materials described above. In various embodiments, thereinforcement material may comprise collagen, gelatin, fibrin,fibrinogen, elastin, keratin, albumin, hydroxyethyl cellulose,cellulose, oxidized cellulose, hydroxypropyl cellulose, carboxyethylcellulose, carboxymethylcellulose, chitan, chitosan, alginate,poly(lactic acid), poly(glycolic acid), poly(hydroxybutyrate),poly(phosphazine), polyesters, polyethylene glycols, polyalkyleneoxides,polyacrylamides, polyhydroxyethylmethylacrylate, polyvinylpyrrolidone,polyvinyl alcohols, poly(caprolactone), poly(dioxanone), polyacrylicacid, polyacetate, polycaprolactone, polypropylene, aliphaticpolyesters, glycerols, poly(amino acids), copoly(ether-esters),polyalkylene oxalates, polyamides, poly(iminocarbonates), polyalkyleneoxalates, polyoxaesters, polyorthoesters, polyphosphazenes andcombinations thereof.

In various embodiments, the tissue thickness compensator may comprise alayer comprising the reinforcement material. In certain embodiments, aporous layer and/or a non-porous layer of a tissue thickness compensatormay comprise the reinforcement material. For example, the porous layermay comprise the reinforcement material and the non-porous layer may notcomprise the reinforcement material. In various embodiments, thereinforcement layer may comprise an inner layer intermediate a firstnon-porous layer and a second non-porous layer. In certain embodiments,the reinforcement layer may comprise an outer layer of the tissuethickness compensator. In certain embodiments, the reinforcement layermay comprise an exterior surface of the tissue thickness compensator.

In various embodiments, the reinforcement material may comprise meshes,monofilaments, multifilament braids, fibers, mats, felts, particles,and/or powders. In certain embodiments, the reinforcement material maybe incorporated into a layer of the tissue thickness compensator. Thereinforcement material may be incorporated into at least one of anon-porous layer and a porous layer. A mesh comprising the reinforcementmaterial may be formed using conventional techniques, such as, forexample, knitting, weaving, tatting, and/or knipling. In variousembodiments, a plurality of reinforcement materials may be oriented in arandom direction and/or a common direction. In certain embodiments, thecommon direction may be one of parallel to the staple line andperpendicular to the staple line, for example. For example, themonofilaments and/or multifilament braids may be oriented in a randomdirection and/or a common direction. The monofilaments and multifilamentbraids may be associated with the non-porous layer and/or the porouslayer. In various embodiments, the tissue thickness compensator maycomprise a plurality of reinforcement fibers oriented in a randomdirection within a non-porous layer. In various embodiments, the tissuethickness compensator may comprise a plurality of reinforcement fibersoriented in a common direction within a non-porous layer.

The fibers may form a non-woven material, such as, for example, a matand a felt. The fibers may have any suitable length, such as, forexample from 0.1 mm to 100 mm and 0.4 mm to 50 mm. The reinforcementmaterial may be ground to a powder. The powder may have a particle sizefrom 10 micrometers to 1 cm, for example. The powder may be incorporatedinto the tissue thickness compensator.

In various embodiments, the tissue thickness compensator may be formedin situ. In various embodiments, the hydrogel may be formed in situ. Thetissue thickness compensator may be formed in situ by covalent, ionic,and/or hydrophobic bonds. Physical (non-covalent) crosslinks may resultfrom complexation, hydrogen bonding, desolvation, Van der Waalsinteractions, ionic bonding, and combinations thereof. Chemical(covalent) crosslinking may be accomplished by any of a number ofmechanisms, including: free radical polymerization, condensationpolymerization, anionic or cationic polymerization, step growthpolymerization, electrophile-nucleophile reactions, and combinationsthereof.

In various embodiments, in situ formation of the tissue thicknesscompensator may comprise reacting two or more precursors that arephysically separated until contacted in situ and/or react to anenvironmental condition to react with each other to form the hydrogel.In situ polymerizable polymers may be prepared from precursor(s) thatcan be reacted to form a polymer at the surgical site. The tissuethickness compensator may be formed by crosslinking reactions of theprecursor(s) in situ. In certain embodiments, the precursor may comprisean initiator capable of initiating a polymerization reaction for theformation of the in situ tissue thickness compensator. The tissuethickness compensator may comprise a precursor that can be activated atthe time of application to create, in various embodiments, a crosslinkedhydrogel. In situ formation of the tissue thickness compensator maycomprise activating at least one precursor to form bonds to form thetissue thickness compensator. In various embodiments, activation may beachieved by changes in the physical conditions, biological conditions,and/or chemical conditions at the surgical site, including, but notlimited to temperature, pH, electric fields, ionic strength, enzymaticand/or chemical reactions, electrical and/or magnetic stimuli, and otherphysiological and environmental variables. In various embodiments, theprecursors may be contacted outside the body and introduced to thesurgical site.

In various embodiments, the tissue thickness compensator may compriseone or more encapsulations, or cells, which can be configured to storeat least one component therein. In certain embodiments, theencapsulation may be configured to store a hydrogel precursor therein.In certain embodiments, the encapsulation may be configured to store twocomponents therein, for example. In certain embodiments, theencapsulation may be configured to store a first hydrogel precursor anda second hydrogel precursor therein. In certain embodiments, a firstencapsulation may be configured to store a first hydrogel precursortherein and a second encapsulation may be configured to store a secondhydrogel precursor therein. As described above, the encapsulations canbe aligned, or at least substantially aligned, with the staple legs topuncture and/or otherwise rupture the encapsulations when the staplelegs contact the encapsulation. In certain embodiments, theencapsulations may be compressed, crushed, collapsed, and/or otherwiseruptured when the staples are deployed. After the encapsulations havebeen ruptured, the component(s) stored therein can flow out of theencapsulation. The component stored therein may contact othercomponents, layers of the tissue thickness compensator, and/or thetissue. In various embodiments, the other components may be flowing fromthe same or different encapsulations, provided in the layers of thetissue thickness compensator, and/or provided to the surgical site bythe clinician. As a result of the above, the component(s) stored withinthe encapsulations can provide expansion and/or swelling of the tissuethickness compensator.

In various embodiments, the tissue thickness compensator may comprise alayer comprising the encapsulations. In various embodiments, theencapsulation may comprise a void, a pocket, a dome, a tube, andcombinations thereof associated with the layer. In certain embodiments,the encapsulations may comprise voids in the layer. In at least oneembodiment, the layer can comprise two layers that can be attached toone another wherein the encapsulations can be defined between the twolayers. In certain embodiments, the encapsulations may comprise domes onthe surface of the layer. For example, at least a portion of theencapsulations can be positioned within domes extending upwardly fromthe layer. In certain embodiments, the encapsulations may comprisepockets formed within the layer. In certain embodiments, a first portionof the encapsulations may comprise a dome and a second portion of theencapsulations may comprise a pocket. In certain embodiments, theencapsulations may comprise a tube embedded within the layer. In certainembodiments, the tube may comprise the non-synthetic materials and/orsynthetic materials described herein, such as PLA. In at least oneembodiment, the tissue thickness compensator may comprise a bioabsorablefoam, such as ORC, comprising PLA tubes embedded therein, and the tubemay encapsulate a hydrogel, for example. In certain embodiments, theencapsulations may comprise discrete cells that are unconnected to eachother. In certain embodiments, one or more of the encapsulations can bein fluid communication with each other via one or more passageways,conduits, and/or channels, for example, extending through the layer.

The rate of release of a component from the encapsulation may becontrolled by the thickness of the tissue thickness compensator, thecomposition of tissue thickness compensator, the size of the component,the hydrophilicity of the component, and/or the physical and/or chemicalinteractions among the component, the composition of the tissuethickness compensator, and/or the surgical instrument, for example. Invarious embodiments, the layer can comprise one or more thin sections orweakened portions, such as partial perforations, for example, which canfacilitate the incision of the layer and the rupture of theencapsulations. In various embodiments, the partial perforations may notcompletely extend through a layer while, in certain embodiments,perforations may completely extend through the layer.

In various embodiments, an anvil may comprise a tissue thicknesscompensator comprising an encapsulated component comprising at least onemicrosphere particle. In certain embodiments, the tissue thicknesscompensator may comprise an encapsulation comprising a firstencapsulated component and a second encapsulated component. In certainembodiments, the tissue thickness compensator may comprise anencapsulation comprising a first microsphere particle and a secondmicrosphere particle.

In various embodiments, the tissue thickness compensator may be suitablefor use with a surgical instrument. As described above the tissuethickness compensator may be associated with the staple cartridge and/orthe anvil. The tissue thickness compensator may be configured into anyshape, size and/or dimension suitable to fit the staple cartridge and/oranvil. As described herein, the tissue thickness compensator may bereleasably attached to the staple cartridge and/or anvil. The tissuethickness compensator may be attached to the staple cartridge and/oranvil in any mechanical and/or chemical manner capable of retaining thetissue thickness compensator in contact with the staple cartridge and/oranvil prior to and during the stapling process. The tissue thicknesscompensator may be removed or released from the staple cartridge and/oranvil after the staple penetrates the tissue thickness compensator. Thetissue thickness compensator may be removed or released from the staplecartridge and/or anvil as the staple cartridge and/or anvil is movedaway from the tissue thickness compensator.

In various embodiments, referring now to FIG. 14, a staple cartridge,such as staple cartridge 10000, for example, can comprise a supportportion 10010 and a compressible tissue thickness compensator 10020.Referring now to FIGS. 16-18, the support portion 10010 can comprise adeck surface 10011 and a plurality of staple cavities 10012 definedwithin the support portion 10010. Each staple cavity 10012 can be sizedand configured to removably store a staple, such as a staple 10030, forexample, therein. The staple cartridge 10000 can further comprise aplurality of staple drivers 10040 which can each be configured tosupport one or more staples 10030 within the staple cavities 10012 whenthe staples 10030 and the staple drivers 10040 are in their unfiredpositions. In at least one such embodiment, referring primarily to FIGS.22 and 23, each staple driver 10040 can comprise one or more cradles, ortroughs, 10041, for example, which can be configured to support thestaples and limit relative movement between the staples 10030 and thestaple drivers 10040. In various embodiments, referring again to FIG.16, the staple cartridge 10000 can further comprise a staple-firing sled10050 which can be moved from a proximal end 10001 to a distal end 10002of the staple cartridge in order to sequentially lift the staple drivers10040 and the staples 10030 from their unfired positions toward an anvilpositioned opposite the staple cartridge 10000. In certain embodiments,referring primarily to FIGS. 16 and 18, each staple 10030 can comprise abase 10031 and one or more legs 10032 extending from the base 10031wherein each staple can be at least one of substantially U-shaped andsubstantially V-shaped, for example. In at least one embodiment, thestaples 10030 can be configured such that the tips of the staple legs10032 are recessed with respect to the deck surface 10011 of the supportportion 10010 when the staples 10030 are in their unfired positions. Inat least one embodiment, the staples 10030 can be configured such thatthe tips of the staple legs 10032 are flush with respect to the decksurface 10011 of the support portion 10010 when the staples 10030 are intheir unfired positions. In at least one embodiment, the staples 10030can be configured such that the tips of the staple legs 10032, or atleast some portion of the staple legs 10032, extend above the decksurface 10011 of the support portion 10010 when the staples 10030 are intheir unfired positions. In such embodiments, the staple legs 10032 canextend into and can be embedded within the tissue thickness compensator10020 when the staples 10030 are in their unfired positions. In at leastone such embodiment, the staple legs 10032 can extend above the decksurface 10011 by approximately 0.075″, for example. In variousembodiments, the staple legs 10032 can extend above the deck surface10011 by a distance between approximately 0.025″ and approximately0.125″, for example. In certain embodiments, further to the above, thetissue thickness compensator 10020 can comprise an uncompressedthickness between approximately 0.08″ and approximately 0.125″, forexample.

In use, further to the above and referring primarily to FIG. 31, ananvil, such as anvil, 10060, for example, can be moved into a closedposition opposite the staple cartridge 10000. As described in greaterdetail below, the anvil 10060 can position tissue against the tissuethickness compensator 10020 and, in various embodiments, compress thetissue thickness compensator 10020 against the deck surface 10011 of thesupport portion 10010, for example. Once the anvil 10060 has beensuitably positioned, the staples 10030 can be deployed, as alsoillustrated in FIG. 31. In various embodiments, as mentioned above, thestaple-firing sled 10050 can be moved from the proximal end 10001 of thestaple cartridge 10000 toward the distal end 10002, as illustrated inFIG. 32. As the sled 10050 is advanced, the sled 10050 can contact thestaple drivers 10040 and lift the staple drivers 10040 upwardly withinthe staple cavities 10012. In at least one embodiment, the sled 10050and the staple drivers 10040 can each comprise one or more ramps, orinclined surfaces, which can co-operate to move the staple drivers 10040upwardly from their unfired positions. In at least one such embodiment,referring to FIGS. 19-23, each staple driver 10040 can comprise at leastone inclined surface 10042 and the sled 10050 can comprise one or moreinclined surfaces 10052 which can be configured such that the inclinedsurfaces 10052 can slide under the inclined surface 10042 as the sled10050 is advanced distally within the staple cartridge. As the stapledrivers 10040 are lifted upwardly within their respective staplecavities 10012, the staple drivers 10040 can lift the staples 10030upwardly such that the staples 10030 can emerge from their staplecavities 10012 through openings in the staple deck 10011. During anexemplary firing sequence, referring primarily to FIGS. 25-27, the sled10050 can first contact staple 10030 a and begin to lift the staple10030 a upwardly. As the sled 10050 is advanced further distally, thesled 10050 can begin to lift staples 10030 b, 10030 c, 10030 d, 10030 e,and 10030 f, and any other subsequent staples, in a sequential order. Asillustrated in FIG. 27, the sled 10050 can drive the staples 10030upwardly such that the legs 10032 of the staples contact the opposinganvil, are deformed to a desired shape, and ejected therefrom thesupport portion 10010. In various circumstances, the sled 10030 can moveseveral staples upwardly at the same time as part of a firing sequence.With regard to the firing sequence illustrated in FIG. 27, the staples10030 a and 10030 b have been moved into their fully fired positions andejected from the support portion 10010, the staples 10030 c and 10030 dare in the process of being fired and are at least partially containedwithin the support portion 10010, and the staples 10030 e and 10030 fare still in their unfired positions.

As discussed above, and referring to FIG. 33, the staple legs 10032 ofthe staples 10030 can extend above the deck surface 10011 of the supportportion 10010 when the staples 10030 are in their unfired positions.With further regard to this firing sequence illustrated in FIG. 27, thestaples 10030 e and 10030 f are illustrated in their unfired positionand their staple legs 10032 extend above the deck surface 10011 and intothe tissue thickness compensator 10020. In various embodiments, the tipsof the staple legs 10032, or any other portion of the staple legs 10032,may not protrude through a top tissue-contacting surface 10021 of thetissue thickness compensator 10020 when the staples 10030 are in theirunfired positions. As the staples 10030 are moved from their unfiredpositions to their fired positions, as illustrated in FIG. 27, the tipsof the staple legs can protrude through the tissue-contacting surface10032. In various embodiments, the tips of the staple legs 10032 cancomprise sharp tips which can incise and penetrate the tissue thicknesscompensator 10020. In certain embodiments, the tissue thicknesscompensator 10020 can comprise a plurality of apertures which can beconfigured to receive the staple legs 10032 and allow the staple legs10032 to slide relative to the tissue thickness compensator 10020. Incertain embodiments, the support portion 10010 can further comprise aplurality of guides 10013 extending from the deck surface 10011. Theguides 10013 can be positioned adjacent to the staple cavity openings inthe deck surface 10011 such that the staple legs 10032 can be at leastpartially supported by the guides 10013. In certain embodiments, a guide10013 can be positioned at a proximal end and/or a distal end of astaple cavity opening. In various embodiments, a first guide 10013 canbe positioned at a first end of each staple cavity opening and a secondguide 10013 can be positioned at a second end of each staple cavityopening such that each first guide 10013 can support a first staple leg10032 of a staple 10030 and each second guide 10013 can support a secondstaple leg 10032 of the staple. In at least one embodiment, referring toFIG. 33, each guide 10013 can comprise a groove or slot, such as groove10016, for example, within which a staple leg 10032 can be slidablyreceived. In various embodiments, each guide 10013 can comprise a cleat,protrusion, and/or spike that can extend from the deck surface 10011 andcan extend into the tissue thickness compensator 10020. In at least oneembodiment, as discussed in greater detail below, the cleats,protrusions, and/or spikes can reduce relative movement between thetissue thickness compensator 10020 and the support portion 10010. Incertain embodiments, the tips of the staple legs 10032 may be positionedwithin the guides 10013 and may not extend above the top surfaces of theguides 10013 when the staples 10030 are in their unfired position. In atleast such embodiment, the guides 10013 can define a guide height andthe staples 10030 may not extend above this guide height when they arein their unfired position.

In various embodiments, a tissue thickness compensator, such as tissuethickness compensator 10020, for example, can be comprised of a singlesheet of material. In at least one embodiment, a tissue thicknesscompensator can comprise a continuous sheet of material which can coverthe entire top deck surface 10011 of the support portion 10010 or,alternatively, cover less than the entire deck surface 10011. In certainembodiments, the sheet of material can cover the staple cavity openingsin the support portion 10010 while, in other embodiments, the sheet ofmaterial can comprise openings which can be aligned, or at leastpartially aligned, with the staple cavity openings. In variousembodiments, a tissue thickness compensator can be comprised of multiplelayers of material. In some embodiments, referring now to FIG. 15, atissue thickness compensator can comprise a compressible core and a wrapsurrounding the compressible core. In certain embodiments, a wrap 10022can be configured to releasably hold the compressible core to thesupport portion 10010. In at least one such embodiment, the supportportion 10010 can comprise one or more projections, such as projections10014 (FIG. 18), for example, extending therefrom which can be receivedwithin one or more apertures and/or slots, such as apertures 10024, forexample, defined in the wrap 10022. The projections 10014 and theapertures 10024 can be configured such that the projections 10014 canretain the wrap 10022 to the support portion 10010. In at least oneembodiment, the ends of the projections 10014 can be deformed, such asby a heat-stake process, for example, in order to enlarge the ends ofthe projections 10014 and, as a result, limit the relative movementbetween the wrap 10022 and the support portion 10010. In at least oneembodiment, the wrap 10022 can comprise one or more perforations 10025which can facilitate the release of the wrap 10022 from the supportportion 10010, as illustrated in FIG. 15. Referring now to FIG. 24, atissue thickness compensator can comprise a wrap 10222 including aplurality of apertures 10223, wherein the apertures 10223 can bealigned, or at least partially aligned, with the staple cavity openingsin the support portion 10010. In certain embodiments, the core of thetissue thickness compensator can also comprise apertures which arealigned, or at least partially aligned, with the apertures 10223 in thewrap 10222. In other embodiments, the core of the tissue thicknesscompensator can comprise a continuous body and can extend underneath theapertures 10223 such that the continuous body covers the staple cavityopenings in the deck surface 10011.

In various embodiments, as described above, a tissue thicknesscompensator can comprise a wrap for releasably holding a compressiblecore to the support portion 10010. In at least one such embodiment,referring to FIG. 16, a staple cartridge can further comprise retainerclips 10026 which can be configured to inhibit the wrap, and thecompressible core, from prematurely detaching from the support portion10010. In various embodiments, each retainer clip 10026 can compriseapertures 10028 which can be configured to receive the projections 10014extending from the support portion 10010 such that the retainer clips10026 can be retained to the support portion 10010. In certainembodiments, the retainer clips 10026 can each comprise at least one panportion 10027 which can extend underneath the support portion 10010 andcan support and retain the staple drivers 10040 within the supportportion 10010. In certain embodiments, as described above, a tissuethickness compensator can be removably attached to the support portion10010 by the staples 10030. More particularly, as also described above,the legs of the staples 10030 can extend into the tissue thicknesscompensator 10020 when the staples 10030 are in their unfired positionand, as a result, releasably hold the tissue thickness compensator 10020to the support portion 10010. In at least one embodiment, the legs ofthe staples 10030 can be in contact with the sidewalls of theirrespective staple cavities 10012 wherein, owing to friction between thestaple legs 10032 and the sidewalls, the staples 10030 and the tissuethickness compensator 10020 can be retained in position until thestaples 10030 are deployed from the staple cartridge 10000. When thestaples 10030 are deployed, the tissue thickness compensator 10020 canbe captured within the staples 10030 and held against the stapled tissueT. When the anvil is thereafter moved into an open position to releasethe tissue T, the support portion 10010 can be moved away from thetissue thickness compensator 10020 which has been fastened to thetissue. In certain embodiments, an adhesive can be utilized to removablyhold the tissue thickness compensator 10020 to the support portion10010. In at least one embodiment, a two-part adhesive can be utilizedwherein, in at least one embodiment, a first part of the adhesive can beplaced on the deck surface 10011 and a second part of the adhesive canbe placed on the tissue thickness compensator 10020 such that, when thetissue thickness compensator 10020 is placed against the deck surface10011, the first part can contact the second part to active the adhesiveand detachably bond the tissue thickness compensator 10020 to thesupport portion 10010. In various embodiments, any other suitable meanscould be used to detachably retain the tissue thickness compensator tothe support portion of a staple cartridge.

In various embodiments, further to the above, the sled 10050 can beadvanced from the proximal end 10001 to the distal end 10002 to fullydeploy all of the staples 10030 contained within the staple cartridge10000. In at least one embodiment, referring now to FIGS. 56-60, thesled 10050 can be advanced distally within a longitudinal cavity 10016within the support portion 10010 by a firing member, or knife bar, 10052of a surgical stapler. In use, the staple cartridge 10000 can beinserted into a staple cartridge channel in a jaw of the surgicalstapler, such as staple cartridge channel 10070, for example, and thefiring member 10052 can be advanced into contact with the sled 10050, asillustrated in FIG. 56. As the sled 10050 is advanced distally by thefiring member 10052, the sled 10050 can contact the proximal-most stapledriver, or drivers, 10040 and fire, or eject, the staples 10030 from thecartridge body 10010, as described above. As illustrated in FIG. 56, thefiring member 10052 can further comprise a cutting edge 10053 which canbe advanced distally through a knife slot in the support portion 10010as the staples 10030 are being fired. In various embodiments, acorresponding knife slot can extend through the anvil positionedopposite the staple cartridge 10000 such that, in at least oneembodiment, the cutting edge 10053 can extend between the anvil and thesupport portion 10010 and incise the tissue and the tissue thicknesscompensator positioned therebetween. In various circumstances, the sled10050 can be advanced distally by the firing member 10052 until the sled10050 reaches the distal end 10002 of the staple cartridge 10000, asillustrated in FIG. 58. At such point, the firing member 10052 can beretracted proximally. In some embodiments, the sled 10050 can beretracted proximally with the firing member 10052 but, in variousembodiments, referring now to FIG. 59, the sled 10050 can be left behindin the distal end 10002 of the staple cartridge 10000 when the firingmember 10052 is retracted. Once the firing member 10052 has beensufficiently retracted, the anvil can be re-opened, the tissue thicknesscompensator 10020 can be detached from the support portion 10010, andthe remaining non-implanted portion of the expended staple cartridge10000, including the support portion 10010, can be removed from thestaple cartridge channel 10070.

After the expended staple cartridge 10000 has been removed from thestaple cartridge channel, further to the above, a new staple cartridge10000, or any other suitable staple cartridge, can be inserted into thestaple cartridge channel 10070. In various embodiments, further to theabove, the staple cartridge channel 10070, the firing member 10052,and/or the staple cartridge 10000 can comprise co-operating featureswhich can prevent the firing member 10052 from being advanced distally asecond, or subsequent, time without a new, or unfired, staple cartridge10000 positioned in the staple cartridge channel 10070. Moreparticularly, referring again to FIG. 56, as the firing member 10052 isadvanced into contact with the sled 10050 and, when the sled 10050 is inits proximal unfired position, a support nose 10055 of the firing member10052 can be positioned on and/or over a support ledge 10056 on the sled10050 such that the firing member 10052 is held in a sufficient upwardposition to prevent a lock, or beam, 10054 extending from the firingmember 10052 from dropping into a lock recess defined within the staplecartridge channel. As the lock 10054 will not drop into the lock recess,in such circumstances, the lock 10054 may not abut a distal sidewall10057 of the lock recess as the firing member 10052 is advanced. As thefiring member 10052 pushes the sled 10050 distally, the firing member10052 can be supported in its upward firing position owing to thesupport nose 10055 resting on the support ledge 10056. When the firingmember 10052 is retracted relative to the sled 10050, as discussed aboveand illustrated in FIG. 59, the firing member 10052 can drop downwardlyfrom its upward position as the support nose 10055 is no longer restingon the support ledge 10056 of the sled 10050. In at least one suchembodiment, the surgical staple can comprise a spring 10058, and/or anyother suitable biasing element, which can be configured to bias thefiring member 10052 into its downward position. Once the firing member10052 has been completely retracted, as illustrated in FIG. 60, thefiring member 10052 cannot be advanced distally through the spent staplecartridge 10000 once again. More particularly, the firing member 10052can't be held in its upper position by the sled 10050 as the sled 10050,at this point in the operating sequence, has been left behind at thedistal end 10002 of the staple cartridge 10000. Thus, as mentionedabove, in the event that the firing member 10052 is advanced once againwithout replacing the staple cartridge, the lock beam 10054 will contactthe sidewall 10057 of the lock recess which will prevent the firingmember 10052 from being advanced distally into the staple cartridge10000 once again. Stated another way, once the spent staple cartridge10000 has been replaced with a new staple cartridge, the new staplecartridge will have a proximally-positioned sled 10050 which can holdthe firing member 10052 in its upper position and allow the firingmember 10052 to be advanced distally once again.

As described above, the sled 10050 can be configured to move the stapledrivers 10040 between a first, unfired position and a second, firedposition in order to eject staples 10030 from the support portion 10010.In various embodiments, the staple drivers 10040 can be contained withinthe staple cavities 10012 after the staples 10030 have been ejected fromthe support portion 10010. In certain embodiments, the support portion10010 can comprise one or more retention features which can beconfigured to block the staple drivers 10040 from being ejected from, orfalling out of, the staple cavities 10012. In various other embodiments,the sled 10050 can be configured to eject the staple drivers 10040 fromthe support portion 10010 with the staples 10030. In at least one suchembodiment, the staple drivers 10040 can be comprised of a bioabsorbableand/or biocompatible material, such as Ultem, for example. In certainembodiments, the staple drivers can be attached to the staples 10030. Inat least one such embodiment, a staple driver can be molded over and/oraround the base of each staple 10030 such that the driver is integrallyformed with the staple. U.S. patent application Ser. No. 11/541,123,entitled SURGICAL STAPLES HAVING COMPRESSIBLE OR CRUSHABLE MEMBERS FORSECURING TISSUE THEREIN AND STAPLING INSTRUMENTS FOR DEPLOYING THE SAME,filed on Sep. 29, 2006, now U.S. Pat. No. 7,794,475, is herebyincorporated by reference in its entirety.

As described above, a surgical stapling instrument can comprise a staplecartridge channel configured to receive a staple cartridge, an anvilrotatably coupled to the staple cartridge channel, and a firing membercomprising a knife edge which is movable relative to the anvil and thestaple cartridge channel. In use, a staple cartridge can be positionedwithin the staple cartridge channel and, after the staple cartridge hasbeen at least partially expended, the staple cartridge can be removedfrom the staple cartridge channel and replaced with a new staplecartridge. In some such embodiments, the staple cartridge channel, theanvil, and/or the firing member of the surgical stapling instrument maybe re-used with the replacement staple cartridge. In certain otherembodiments, a staple cartridge may comprise a part of a disposableloading unit assembly which can include a staple cartridge channel, ananvil, and/or a firing member, for example, which can be replaced alongwith the staple cartridge as part of replacing the disposable loadingunit assembly. Certain disposable loading unit assemblies are disclosedin U.S. patent application Ser. No. 12/031,817, entitled END EFFECTORCOUPLING ARRANGEMENTS FOR A SURGICAL CUTTING AND STAPLING INSTRUMENT,which was filed on Feb. 15, 2008, now U.S. Patent ApplicationPublication No. 2009/0206131, the entire disclosure of which isincorporated by reference herein.

In various embodiments, the tissue thickness compensator may comprise anextrudable, a castable, and/or moldable composition comprising at leastone of the synthetic and/or non-synthetic materials described herein. Invarious embodiments, the tissue thickness compensator may comprise afilm or sheet comprising two or more layers. The tissue thicknesscompensator may be obtained using conventional methods, such as, forexample, mixing, blending, compounding, spraying, wicking, solventevaporating, dipping, brushing, vapor deposition, extruding,calendaring, casting, molding and the like. In extrusion, an opening maybe in the form of a die comprising at least one opening to impart ashape to the emerging extrudate. In calendering, an opening may comprisea nip between two rolls. Conventional molding methods may include, butare not limited to, blow molding, injection molding, foam injection,compression molding, thermoforming, extrusion, foam extrusion, filmblowing, calendaring, spinning, solvent welding, coating methods, suchas dip coating and spin coating, solution casting and film casting,plastisol processing (including knife coating, roller coating andcasting), and combinations thereof. In injection molding, an opening maycomprise a nozzle and/or channels/runners and/or mold cavities andfeatures. In compression molding, the composition may be positioned in amold cavity, heated to a suitable temperature, and shaped by exposure tocompression under relatively high pressure. In casting, the compositionmay comprise a liquid or slurry that may be poured or otherwise providedinto, onto and/or around a mold or object to replicate features of themold or object. After casting, the composition may be dried, cooled,and/or cured to form a solid.

In various embodiments, a method of manufacturing a tissue thicknesscompensator comprising at least one medicament stored and/or absorbedtherein may generally comprise providing a tissue thickness compensatorand contacting the tissue thickness compensator and the medicament toretain the medicament in the tissue thickness compensator. In at leastone embodiment, a method of manufacturing a tissue thickness compensatorcomprising an antibacterial material may comprise providing a hydrogel,drying the hydrogel, swelling the hydrogel in an aqueous solution ofsilver nitrate, contacting the hydrogel and a solution of sodiumchloride to form the tissue thickness compensator having antibacterialproperties. The tissue thickness compensator may comprise silverdispersed therein.

In various embodiments, referring now to FIG. 116, a tissue thicknesscompensator, such as tissue thickness compensator 22020, for example,can be attached to an anvil of a surgical stapling instrument, such asanvil 22060, for example. The tissue thickness compensator 22020 caninclude, in at least one embodiment, a cavity 22024 defined between afirst film 22026 and a second film 22027, wherein at least portions ofthe first film 22026 are attached to the second film 22027. In at leastone such embodiment, the first film 22026 can be attached to the secondfilm 22027 along lateral seams 22028 a and 22028 b, for example. Invarious embodiments, the first film 22026 can be attached to the secondfilm 22027 along a sealed perimeter in order to sealingly enclose thecavity 22024. In certain embodiments, the first film 22026 and thesecond film 22027 can be thermally welded along the lateral seams 22028a, 22028 b and/or any other seams connecting the films 22026 and 22027,for example. Referring again to FIG. 116, the anvil 22060 can comprise aplurality of staple forming pockets 22062 which can each be configuredto receive and deform the leg of staple wherein, in at least oneembodiment, the second film 22027 can comprise projections 22022 whichcan extend into the forming pockets 22062. In certain embodiments, theprojections 22022 can be sized and configured such that they fit snuglywithin the forming pockets 22062 and can retain the tissue thicknesscompensator 22020 to the anvil 22060. In the illustrated embodiment, theanvil 22060 can comprise six rows of forming pockets 22062 wherein thetissue thickness compensator 22020 can similarly comprise six rows ofprojections 22022 which are aligned with the forming pockets 22062, forexample. Other embodiments comprising more than or less than six rows offorming pockets 22062 and/or projections 22022 could be utilized. Incertain embodiments, one or more adhesives could be utilized to retainthe tissue thickness compensator 22020 to the anvil 20060.

As discussed above, the tissue thickness compensator 22020 can comprisea cavity 22024 defined therein. In various embodiments, the cavity 22024can extend longitudinally along the anvil 22060. Referring again to FIG.116, the tissue thickness compensator 22020 can comprise a compressiblematerial positioned within the cavity 22024. In at least one embodiment,referring now to FIG. 117, staples, such as staples 22030, for example,can be ejected from a staple cartridge such that the staples 22030penetrate the tissue T and then penetrate the tissue thicknesscompensator 22020 before contacting the anvil 22060. As the legs of thestaples 22030 are deformed by the anvil 22060, in various embodiments,the legs can be turned downwardly to repenetrate the tissue thicknesscompensator 22020 once again. In any event, once the staples 22030 havepenetrated the tissue thickness compensator 22020, one or more fluidscontained in the cavity 22024, for example, can flow or weep out of thetissue thickness compensator 22020 and onto the tissue T. In certainembodiments, the cavity 22024 can comprise one or more powders containedtherein which can escape the cavity 22024 once the tissue thicknesscompensator 22020 has been at least partially ruptured by the staples22030, for example. In various embodiments, a material 22025 positionedwithin the cavity 22024 can be compressed or squeezed within the staples22030 when the staples 22030 are deformed into their firedconfigurations such that, in at least one embodiment, a fluid storedwithin the material 22025 can be expressed from the material 22025, forexample. In various embodiments, referring again to FIG. 117, thestaples 22030 can also be configured to capture a tissue thicknesscompensator, such as compensator 22029, for example, removably attachedto the staple cartridge against the other side of the tissue T.

In various embodiments, further to the above, the material 22025 cancomprise freeze-dried thrombin, freeze-dried fibrin, and/or small fibernon-woven oxidized regenerated cellulose, for example. In certainembodiments, the material 22025 can comprise a compressed powder wafer.In at least one embodiment, the sealed cavity 22024 can comprise aninternal atmosphere having a pressure below that of the atmospheresurrounding the tissue thickness compensator 22020. In such anembodiment, the pressure difference between the atmosphere in theinternal cavity 22024 and the atmosphere can cause the films 22027 and22028 to be drawn inwardly. When the internal cavity 22024 is rupturedby the staples 22030, as described above, the vacuum within the internalcavity 22024 can equalize with the surrounding atmosphere and thematerial 22025 can escape the internal cavity 22024, as also describedabove. In such circumstances, the tissue thickness compensator 22020 canexpand and apply a compressive force to the tissue T captured within thestaples 20030. In embodiments in which the material 22025 isvacuum-packed within the tissue thickness compensator 22020, thematerial 22025 can expand after the internal cavity 22024 has beenpunctured. In certain embodiments, the films 22026, 22027 can becomprised of a bioabsorbable material and can be configured to dissolveonce placed in the patient. In at least one such embodiment, each film22026, 22027 can be comprised of a layer, or laminate, which is betweenapproximately 0.25 mils and approximately 0.50 mils thick, for example.In any event, further to the above, the tissue thickness compensator22020, including the material 22025, can be transected by a cuttingelement as the staples 22030 are fired from their staple cartridge.

In certain embodiments, referring again to FIG. 116, the cavity 22024and the material 22025 of the tissue thickness compensator 22020 can bepositioned underneath the inner four rows of staple forming pockets22062 while the seams 22028 a, 22028 b can be positioned underneath theouter rows of forming pockets 22062. In such embodiments, the staples inthe outer rows of staples may not engage the material 22025 and, thus,they may not capture the material 22025 therein. Rather, such staplesmay only capture the films 22026 and 22027 along seams 22028 a, 22028 b.In various alternative embodiments, referring now to FIGS. 118 and 119,a tissue thickness compensator 22120 can comprise, similar to the above,a first film 22126, a second film 22127, and a plurality of materials22125 a-d captured between the first film 22126 and the second film22127. In at least one such embodiment, referring primarily to FIG. 118,the first material 22125 a can be aligned with an outer row of staples22030 in staple cartridge 22000 and an outer row of staple cavities22062 in anvil 22060, the second material 22125 b and the third material22125 c can each be aligned with two inner rows of staples 22030 andstaple cavities 22062, and the fourth material 22126 d can be alignedwith another outer row of staples 22030 and staple cavities 22062. Insuch an embodiment, referring now to FIG. 119, all of the staples 22030can be arranged such that they can capture at least one of the materials22125 a-22125 d therein. As illustrated in FIGS. 118 and 119, further tothe above, the staples 22030 can be lifted upwardly between an unfiredposition and a fired position by staple drivers 22040 positioned withinthe staple cartridge 22000.

In various embodiments, referring again to FIGS. 118 and 119, the layers22126 and 22127 can define one or more sealed cavities in which thematerials 22125 a-d can be positioned. In at least one embodiment, thelayers 22126 and 22127 can be sealed together along a perimeter whichcan include lateral seams 22128 a and 22128 b, for example, utilizingany suitable process, such as thermal and/or laser welding, for example.In certain embodiments, each of the materials 22125 a-22125 d can besealed within separate cavities while, in other embodiments, two or moreof the materials 22125 a-22125 d can be sealed within the same cavity.In various embodiments, the materials 22125 a-22125 d can be comprisedof the same material or materials while, in other embodiments, one ormore of the materials 22125 a-22125 d can be comprised of differentmaterials. In at least one embodiment, one or more of the materials22125 a-22125 d can be comprised of sodium sterate and/or LAE, forexample. In certain embodiments, the materials 22125 a-22125 d cancomprise a lubricant. In such embodiments, the legs of the staples 22030can be exposed to the lubricant when the staple legs penetrate thematerials 22125 a-22125 d of the tissue thickness compensator 22120.After the legs pass through the tissue thickness compensator 22120, thelegs can contact the anvil 22060 wherein the lubricant can reduce thecoefficient of friction, and the friction forces, between the staplelegs and the anvil 22060. In such circumstances, the force needed tofire the staples 22030 can be reduced. Owing to the position of thetissue thickness compensator 22120 against the anvil 22060, in at leastone embodiment, the staple legs of the staples 22030 can contact theanvil 22060 directly after exiting the tissue thickness compensator22120 thereby reducing the possibility that the lubricant may be wipedoff the staple legs before they contact the anvil 22060. Similarly, thestaple legs of the staples 22030 can contact the anvil 22060 directlyafter being exposed to one or medicaments in the tissue thicknesscompensator 22120 thereby reducing the possibility that medicaments maybe wiped off the staple legs before they re-enter the tissue T. In somecircumstances, the staple legs can re-enter the tissue thicknesscompensator 22120 as the staple legs are being deformed downwardly suchthat the staple legs can be re-exposed to the medicaments beforere-entering the tissue T, for example. In various embodiments, similarto the above, the second film 22127 can comprise a plurality ofprojections 22122, for example, which can be snugly received within thestaple cavities 22062 in order to retain the tissue thicknesscompensator 22120 to the anvil 22060, for example.

In various embodiments, referring now to FIGS. 120 and 121, an endeffector of a surgical stapling instrument can comprise a tissuethickness compensator, such as compensator 22220, for example, which cancomprise a plurality of cavities 22222 aligned with the staple formingpockets 22062 of the anvil 22060. In at least one embodiment, thecompensator 22220 can be comprised of a first, or bottom, layer 22226and a second, or top, layer 22227 wherein the first layer 22226 and/orthe second layer 22227 can comprise a plurality of raised portions orpartial bubbles which can define the cavities 22222. As illustrated inFIG. 120, the compensator 22220 can be attached to the anvil 22060 suchthat the cavities 22222 are aligned, or at least substantially aligned,with the staple forming pockets 22062 of the anvil 22060. In variousembodiments, each cavity 22222 can include one or more medicamentscontained therein, such as, for example, oxidized regenerated cellulose,calcium, and/or alginate. In use, in certain embodiments, each cavity22222 can be in a sealed, unpunctured state prior to being punctured bythe staples 22030 ejected from the staple cartridge 22000, for example.After the legs of the staples 22030 have passed through the tissue T,referring now to FIG. 121, each staple leg can pierce and penetrate thefirst layer 22226 and enter into a cavity 22222 where the staple leg canthen pass through one or more medicaments contained therein beforepiercing and penetrating the second layer 22227. Similar to the above,the legs of the staples 22030 can then contact the anvil 22060.

In various embodiments, the cavities 22222 can maintain the one or moremedicaments stored therein in a dry or an at least substantially drystate before being ruptured. After a cavity 22222 has been ruptured, afluid, such as blood, for example, can enter into the cavity 22222 andmix with the one or more medicaments. In at least one embodiment, themixture of the fluid with a medicament can cause the medicament toexpand within the cavity 22222 wherein, in at least one such embodiment,the medicament can comprise at least one hydrogel, for example. Incertain embodiments, the medicament can comprise at least onehaemostatic material, for example. In various embodiments, the firstlayer 22226 and/or the second layer 22227 can be comprised of a flexiblematerial which can stretch to accommodate the expansion of themedicament. In at least one embodiment, the layers 22226, 22227 can becomprised of a CAP/GLY material, for example. In any event, theexpansion of the medicament can apply a compressive force to the tissueT captured within and/or positioned around the staples 22030, forexample. In various circumstances, the expansion of the medicament cancause the cavities 22222 to burst. In certain embodiments, a first groupof cavities 22222 can comprise a first medicament therein while a secondgroup of cavities 22222 can comprise a second medicament therein, forexample. In at least one such embodiment, the first medicament can beconfigured to expand a first amount and/or at a first rate while thesecond medicament can be configured to expand a second amount and/or ata second rate, for example, wherein the first amount can be differentthan the second amount and/or the first rate can be different than thesecond rate. Further to the above, in various embodiments, one or morecavities 22222 can include two or more medicaments stored in each cavitywherein the medicaments can comprise a first medicament and a secondmedicament, for example. In certain embodiments, a cavity 22222 canmaintain the first medicament and the second medicament in a dry, or anat least substantially dry, state before being ruptured. After thecavity 22222 has been ruptured, as described above, blood, for example,can enter into the cavity 22222 and mix with the first and secondmedicaments wherein, in at least one embodiment, the first and secondmedicaments can form a gel which expands.

In various embodiments, referring now to FIGS. 122-124, a tissuethickness compensator, such as compensator 22320, for example, cancomprise a plurality of first cavities 22322 a and a plurality of secondcavities 22322 b which can be aligned with staple forming pockets 22062a and 22062 b, respectively. In at least one embodiment, referringprimarily to FIG. 123, the staple forming pockets 22062 a and 22062 bmay be defined in separate stepped surfaces on the anvil 22060. Moreparticularly, the forming pockets 22062 a can be defined in firstsurfaces 22069 a of anvil 22060 and the forming pockets 22062 b can bedefined in second surfaces 22069 b wherein the first surfaces 22069 acan be positioned offset, or higher, with respect to the second surfaces22069 b, for example. In various embodiments, the first cavities 22322 aof the tissue thickness compensator 22320 can be larger than the secondcavities 22322 b wherein, in at least one such embodiment, the firstcavities 22322 a can extend higher than the second cavities 22322 b. Asa result of the above, the first cavities 22322 a can extend upwardlyinto the first staple forming pockets 22062 a while, concurrently, thesecond cavities 22322 b can extend upwardly into the second stapleforming pockets 22062 b. In various embodiments, each of the firstcavities 22322 a can be configured to contain a larger quantity of amedicament than the second cavities 22322 b, for example. In otherembodiments, the first cavities 22322 a and the second cavities 22322 bcan contain the same, or at least substantially the same, amount ofmedicament therein eventhough the cavities 22322 a and 22322 b may havedifferent sizes.

In various embodiments, further to the above, the first cavities 22322 acan be arranged in certain rows while the second cavities 22322 b can bearranged in different rows. In certain embodiments, a tissue thicknesscompensator can comprise cavities aligned with each forming pocketwhile, in other embodiments, referring to FIG. 130, a tissue thicknesscompensator, such as compensator 22420, for example, may comprisecavities aligned with only some of the forming pockets. In variousembodiments, referring again to FIG. 123, the compensator 22320 can beattached to the anvil 22060. In at least one embodiment, the cavities22322 a and/or the cavities 22322 b can be configured such that fitsnugly within staple forming pockets 22062 a and/or 22062 b,respectively. In certain embodiments, the compensator 22320 can beassembled to the anvil 22060 such that the second layer 22327 of thecompensator 22320 is positioned against the second surfaces 22069 b ofthe anvil 22060. In certain other embodiments, referring now to FIGS.125 and 126, the compensator 22320 can be positioned adjacent to theanvil 22060 such that the compensator 22320 can abut the anvil 22060when the anvil 22060 is displaced toward the staple cartridge 22000 tocompress the tissue T therebetween. Once the staples 22030 have beenfired from the staple cartridge 22000 and deformed by the anvil 22060,referring now to FIG. 127, the compensator 22320 can be trapped againstthe tissue T by the staples 22030 and the anvil 22060 can be moved awayfrom the compensator 22320. In certain circumstances, referring now toFIG. 128, one or more of the staples 22030 may not be properly deformedby the anvil 22030. In such circumstances, referring now to FIG. 129,the cavities in the tissue thickness compensator which overlie themisfired or misformed staples may not be pierced when the staples arefired. In at least one such embodiment, the tissue thickness compensatormay be comprised of a bioabsorbable material which can dissolve andsubsequently release the medicament contained in the unpierced cavities.

In various embodiments, further to the above, the first cavities 22322 aand/or the second cavities 22322 b of the tissue thickness compensator22320 can comprise a gas, such as air, carbon dioxide, and/or nitrogen,for example, sealed therein. In certain embodiments, the cavities 22322a and/or 22322 b can comprise bubbles which can be popped when thestaples 22030 are fired through the cavities 22322 a and 22322 b torelease the gas contained therein. In at least one embodiment, suchpopping can provide an audio feedback to the surgeon that the cavities22322 a and 22322 b are being ruptured. In some circumstances, however,some of the staples 22030 may be misfired, as described above, and thecavities 22322 a and 22322 b associated therewith may not be popped. Invarious circumstances, the surgeon can scan the stapled tissue for anyunpopped bubbles, or cavities 22322 a and 22322 b, and determine whetherany corrective action needs to be taken.

As discussed above, referring now to FIG. 131, a surgical staplinginstrument can comprise a firing member, such as firing member 22080,for example, which can include a cutting member, or cutting edge, 22081which can be advanced through the tissue T and one or more tissuethickness compensators as the firing member 22080 is advanced throughthe cartridge 22000 to deploy the staples 22030 therefrom. In variousembodiments, referring primarily to FIG. 133, a compensator, such ascompensator 22520, for example, can be attached to the anvil 22060 ofthe surgical stapling instrument wherein the anvil 22060 can include aknife slot 22061 sized and configured to receive at least a portion ofthe cutting member 22081. Similarly, the staple cartridge 22000 cancomprise a knife slot 22011 which can also be sized and configured toreceive at least a portion of the cutting member 22081. In variousembodiments, referring again to FIG. 131, the compensator 22520 cancomprise one or more cavities, such as cavities 22522, for example,positioned along a cutting line 22521 of the compensator 22520 whereinthe cavities 22522 can be aligned with the knife slot 22061 defined inthe anvil 22060. As the cutting member 22081 is progressed distallythrough the staple cartridge 22000 to deploy the staples 22030, thecutting member 22081 can incise the tissue T and the cavities 22522 ofthe compensator 22520. Similar to the above, referring primarily to FIG.132, each cavity 22522 can define a sealed cavity 22524 which cancontain one or more medicaments 22525 therein. In at least oneembodiment, one or more of the cavities 22522 can be configured tocontain a fluid which can be released when the cavities 22522 are atleast partially incised by the cutting member 22081. In variouscircumstances, the cutting member 22081 can sequentially incise thecavities 22522 and, as a result, sequentially release the medicamentscontained therein.

In various embodiments, referring primarily to FIG. 133, the compensator22520 can comprise lateral projections, or wings, 22529 that extendalong the sides thereof. In at least one embodiment, the projections22529 can be secured to the anvil surfaces 22069 a and/or anvil surfaces22069 b utilizing one or more adhesives, for example. In certainembodiments, the projections 22522 can be sized and configured to fitsnugly within the knife slot 22061 of the anvil 22060 such that, in atleast one such embodiment, the projections 22522 can retain thecompensator 22520 to the anvil 22060. In various embodiments, thelateral projections 22529 can be sized and configured such that theyextend over, or overlie, the staple forming pockets 22062 b and/or thestaple forming pockets 22062 a. In certain other embodiments, referringnow to FIGS. 134 and 135, a compensator 22620 can comprise lateralprojections 22629 that do not extend over, or overlie, the stapleforming pockets 22062 a and 22062 b of the anvil 22060 and/or any otherstaple forming pockets, for example. In at least one such embodiment,the compensator 22620 may not be captured within a staple 22030 ejectedfrom the staple cartridge 22030. In any event, referring again to FIG.131, the cutting member 22081 can transect the compensator 22520 as thecompensator 22520 is being secured to the tissue T by the staples 22030.In such embodiments, the compensator 22520 can detach from the anvil22060 and remain with the tissue T. Referring again to the compensator22620 illustrated in FIGS. 134 and 135, the staples 22030 may not securethe compensator 22620 to the anvil 22060 and, in at least oneembodiment, may remain attached to the anvil 22060 after the cuttingmember 22081 has transected the compensator 22620.

In various embodiment, referring now to FIGS. 136 and 137, an endeffector of a surgical stapling instrument can comprise a tissuethickness compensator, such as compensator 22720, for example, which canbe attached to, or can be configured to be attached to, an anvil, suchas anvil 22760, among others. In at least one embodiment, similar to theabove, the anvil 22760 can comprise a plurality of staple formingpockets 22762 and a longitudinal knife slot 22761 configured to receivea cutting member therein as the cutting member is advanced through theend effector. In certain embodiments, the compensator 22720 can comprisea first film layer 22726 and a second film layer 22727 which can beattached to one another to define a cavity 22724. In at least one suchembodiment, the first film layer 22726 can be attached to the secondfilm layer 22727 along a sealed outer perimeter 22728 wherein the sealedouter perimeter 22728 can contain at least one medicament 22725 in thecavity 22724, for example. As illustrated in FIG. 137, the cavity 22724and the medicament 22725 can extend under all of the staple cavities22762 and, in at least one embodiment, the sealed perimeter 22728 can bepositioned laterally with respect to the outermost staple cavities22762. In various embodiments, the compensator 22720 can furthercomprise a longitudinal rib 22721, for example, which can be configuredto extend upwardly into the knife slot 22761. In at least one suchembodiment, the rib 22721 can be sized and configured to fit snuglywithin the knife slot 22761 in order to secure the compensator 22720 tothe anvil 22760. In certain embodiments, the rib 22721 can be configuredto align or center the compensator 22720 with the anvil 22760.Similarly, referring to FIG. 138, a tissue thickness compensator 22820can comprise a retention rib 22821 which can be positioned within theknife slot 22761, for example, in order to secure the compensator 22820to the anvil 22760. Referring again to FIG. 137, as a cutting member isadvanced through the knife slot 22761, in various circumstances, thecutting member can transect the rib 22721 and release the compensator22720 from the anvil 22760. Such a cutting member is depicted in FIG.138 as part of firing member 22080, for example.

In various embodiments, referring again to FIG. 138, the tissuethickness compensator 22820 can comprise a first layer 22826 and asecond layer 22827 which can be configured and arranged to define aplurality of first packets 22824 a and a plurality of second packets22824 b. In at least one embodiment, each of the first packets 22824 acan be configured to contain a first medicament and each of the secondpackets 22824 b can be configured to contain a second medicament,wherein the second medicament can be different than the firstmedicament. In various embodiments, the first packets 22824 a and thesecond packets 22824 b can be arranged in an alternating arrangement. Inat least one such embodiment, the first packets 22824 a and the secondpackets 22824 b can extend laterally across the tissue thicknesscompensator 22820 such that a second packet 22824 b is positionedintermediate two first packets 22824 a and a first packet 22824 a ispositioned intermediate two second packets 22824 b, for example. As thecutting member 22080 is progressed through the compensator 22820, asillustrated in FIG. 138, the cutting member 22080 can transect a firstpacket 22824 a, followed by a second packet 22824 b, followed by a firstpacket 22824 a, followed by a second packet 22824 b, and so forth.Correspondingly, in such embodiments, the cutting member 22080 cansequentially release the first medicament contained in a first packet22824 a and the second medicament contained in a second packet 22824 bin an alternating arrangement, for example. In embodiments where thefirst packets 22824 a and the second packets 22824 b are positionedadjacent to one another, the first medicament can be configured to mixwith the second medicament when they are released from their respectivefirst packets 22824 a and second packets 22824 b. In at least one suchembodiment, the advancement of the cutting member through thecompensator 22820 can mix the first medicament with the secondmedicament.

In various embodiments, further to the above, the first medicament cancomprise a first powder while the second medicament can comprise asecond powder. In at least one embodiment, the first medicament and/orthe second medicament can be comprised of a haemostatic material,oxidized regenerated cellulose, alginate, and/or calcium, for example.In certain embodiments, the first medicament and/or the secondmedicament can comprise a fluid. In at least one embodiment, one or moreof the first packets 22824 a and/or one or more of the second packets22824 b can comprise a lubricant which can reduce the force needed toadvance the firing member 22080 through the compensator 22820 and/or thetissue T. In various embodiments, the first film layer 22826 and/or thesecond film layer 22827 can be comprised of a bioabsorbable material,such as PDS, for example. In certain embodiments, the first film layer22826 and the second film layer 22827 can be attached to one anothersuch that the first packets 22824 a are sealed from the second packets22824 b prior to being incised by the firing member 22080. In certainembodiments, the first packets 22824 a and/or the second packets 22825 bcan comprise a certain burst strength in order to withstand a certainburst pressure. More particularly, when an anvil, such as anvil 22760,for example, moves the compensator 22820 toward a staple cartridgepositioned opposite the anvil 22760, the packets 22824 a, 22824 b can bepositioned against the tissue positioned intermediate the packets 22824a, 22824 b and the staple cartridge wherein the anvil 22760 can then bepushed, or clamped, downwardly toward the staple cartridge in order tocompress the tissue positioned therebetween. In such circumstances, thepackets 22824 a, 22824 b may be subjected to compressive pressures. Insome circumstances, it may be desirable for the packets 22824 a and/orpackets 22824 b to remain intact until they are incised by the cuttingmember 22080 and/or punctured by staples fired from the staplecartridge. In certain other circumstances, it may be desirable for thepackets 22824 a and/or the packets 22824 b to burst from the compressiveclamping load applied thereto.

As discussed above, the first packets 22824 a and the second packets22842 b can extend laterally across the compensator 22820. In variousembodiments, the first packets 22824 a can extend along transverse axes22823 a while the second packets 22824 b can extend along transverseaxes 22823 b, for example. In at least one embodiment, the first axes22823 a and/or the second axes 22823 b can be perpendicular, or at leastsubstantially perpendicular, to a longitudinal axis 22083 of thecompensator 22820. In at least one such embodiment, the longitudinalaxis 22083 can define the cutting path of the firing member 22080. Incertain embodiments, the first axes 22823 a and/or the second axes 22823b may not be perpendicular to the longitudinal axis 22083 and may beskew with respect to the longitudinal axis 22083. In variousembodiments, as discussed above, the first packets 22824 a and thesecond packets 22824 b can be arranged in an alternating arrangement. Incertain other embodiments, any other suitable arrangement of the firstpackets 22824 a and the second packets 22824 b may be utilized. Forinstance, a sequence of packets arranged in a tissue thicknesscompensator could include a first packet 22824 a, a second packet 22824b, a second packet 22824 b, and a first packet 22824 a. In certainembodiments, a tissue thickness compensator can further comprise aplurality of third packets comprising a third medicament which isdifferent than the first medicament and the second medicament. In atleast one such embodiment, the first packets, the second packets, andthe third packets can be arranged in an alternating arrangement. Forinstance, a sequence of packets arranged in a tissue thicknesscompensator could include a first packet, followed by a second packet,which is followed by a third packet, for example.

In various embodiments, referring again to FIG. 138, the first packets22824 a and/or the second packets 22824 b of the tissue thicknesscompensator 22820 can define U-shaped, or at least substantiallyU-shaped, cross-sections, for example. In certain embodiments, referringnow to FIG. 139, the packets 22924 of a tissue thickness compensator22920 can define circular, or at least substantially circular,cross-sections, for example. In some embodiments, referring now to FIG.140, the packets 23024 of a tissue thickness compensator 23020 candefine oval and/or elliptical cross-sections, for example. In variousembodiments, referring again to FIG. 138, the first cavities 22824 a andthe second cavities 22824 b can comprise symmetrical, or at least nearlysymmetrical, configurations which are defined in parallel, or at leastsubstantially parallel, rows. In certain other embodiments, referringnow to FIG. 141, a tissue thickness compensator, such as compensator23120, for example, can comprise asymmetrical cavities 23122 definedtherein which can have an irregular and/or non-repeating pattern, forexample. In at least one such embodiment, each of the cavities 23122 cancontain one or more different medicaments therein.

In various embodiments, referring now to FIG. 142, a tissue thicknesscompensator, such as tissue thickness compensator 23220, for example,can comprise a casing 23226 which defines a cavity 23224 therein and amaterial 23225 positioned within the cavity 23224. In certainembodiments, the casing 23226 can be comprised of a resorbable polymer,PDS, PGA, PLLA, Cap Gly, and/or PCL, for example, while the material23225 could be comprised of a haemostatic agent, oxidized regeneratedcellulose, Hercules, fibrin, and/or thrombin, for example, which cantake any suitable form such as a powder, a fiber, and/or a gel, forexample. In at least one embodiment, the casing 23226 can bemanufactured utilizing an extrusion process. In such embodiments, thecasing 23226 can comprise a constant, or an at least substantiallyconstant, cross-section along the length thereof which can be createdwithout having to weld a seam together. In at least one such embodiment,the cavity 23224 can be defined by a sidewall extending around theentire perimeter thereof without openings defined therein. In certainembodiments, the casing 23226 can be comprised of a mesh and/or astraw-like material having openings defined therein. In at least oneembodiment, openings can be cut in the casing 23226 by a laser cuttingprocess and/or a die cutting process, for example.

As part of manufacturing the material 23225, referring now to FIGS.145-147, a yarn strand can be created utilizing fibers and/or a fibrousmaterial, such as oxidized regenerated cellulose, for example. Incertain embodiments, longer fibers 23325, depicted in FIG. 145, andshorter fibers 23425, depicted in FIG. 146, can be mixed together asillustrated in FIG. 147 to form the yarn strand of material 23225. Invarious embodiments, the yarn strand can be drawn and/or placed undertension in order to stretch the fibers contained therein in alongitudinal direction. In certain embodiments, referring now to FIG.148, the yarn strand of material 23225 can be fluffed by graspers 23290which can grasp and twist the material 23225 to increase the volume ofthe yarn strand. In at least one such embodiment, the graspers 23290 canfluff the material 23225 as the yarn strand is moving relative to thegraspers 23290, for example. In some embodiments, referring again toFIG. 148, cutting members 23291 could be utilized to make smallincisions and/or micro-cuts, for example, in the yarn strand of material23225. Similar to the above, the cutting members 23291 can cut thematerial 23225 as the yarn strand is moving relative to the cuttingmembers 23291. In certain embodiments, the yarn strand of material 23225can be fluffed before the above-described incisions are made while, inother embodiments, the yarn strand of material 23225 could be incisedbefore it is fluffed.

Once the yarn strand of material 23225 has been suitably prepared, thematerial 23225 can be positioned within the casing 23226. In at leastone embodiment, referring now to FIG. 149, two or more casings 23226could be formed together as part of an extrusion process, discussedabove, wherein the casings 23226 can be connected together as part of atube 23227. In various embodiments, the yarn strand of material 23225can be positioned within, or drawn into, the cavity 23224 defined in thetube 23227. In at least one embodiment, the yarn strand of material23225 can be positioned adjacent to and/or within a first open end 23221of the cavity 23224 wherein a grasper 23292 can be inserted through asecond open end 23222 of the cavity 23224. The grasper 23292 can then bepushed through the cavity 23224 until the jaws 23292 a of the grasper23292 pass through, and/or are positioned relative to, the first openend 23222 such that grasper jaws 23292 a can be manipulated to grasp theyarn strand of material 23225. In certain embodiments, a grasper maycomprise a hook member, for example, which can be configured to graspthe yarn strand of material 23225. In any event, once the grasper 23292has sufficiently grasped the yarn strand of material 23225, the grasper23292 can be drawn back into the cavity 23224 in order to pull the yarnstrand of material 23225 into the cavity 23224. In various embodiments,the grasper 23292 can be configured to twist the yarn strand of material23225 before, during, and/or after the yarn strand is pulled into thetube 23227.

Once the yarn strand of material 23225 has been suitably positionedwithin the tube 23227, the grasper 23292 can then be operated to releasethe yarn strand of material 23225. In various embodiments, the yarnstrand can be released before the yarn strand has been pulled throughthe second open end 23222 of the tube 23227 while, in other embodiments,the yarn strand can be released after the yarn strand has been pulledthrough the second open end 23222, as illustrated in FIG. 150. Incertain circumstances, the yarn strand can be pulled through the secondopen end 23222 such that, when the yarn strand is released, the yarnstrand can shrink, or spring back, into the tube 23227 through thesecond open end 23222. In various circumstances, the yarn strand can becut at a location adjacent to the first open end 23221 such that,similar to the above, the yarn strand can shrink, or spring back, intothe tube 23227 through the first open end 23222. In variouscircumstances, further to the above, the grasper 23292 can apply atension force to the yarn strand of material 23225 such that when thegrasper 23292 releases the yarn strand and/or when the yarn strand iscut, the tension force within the yarn strand can be relieved therebyallowing the yarn strand to contract.

Once the yarn strand of material 23225 has been sufficiently positionedwithin the tube 23227, referring now to FIG. 151, the tube 23227 and thematerial 23225 can be cut into a plurality of segments, wherein eachsegment can be made into a tissue thickness compensator 23220, forexample. In various embodiments, the cavity 23224 extending through thecover 23226 of each such segment can comprise an open end on oppositeends thereof. In at least one such embodiment, one or both of the openends can be closed and/or sealed by a heat-staking, heat-welding, and/orlaser welding process, for example. Referring to FIG. 152, a segmentcomprising a cover 23226 and a portion of the material 23225 therein canbe positioned within a die configured to close and/or seal the open endsof the cover 23226. More particularly, in at least one embodiment, thedie can comprise a base 23294 and a movable portion 23296, for example,wherein the segment can be positioned within a cavity 23295 defined inthe base 23294. Once positioned, the movable portion 23296 can be moveddownwardly to apply a force to the segment. In various embodiments, heatcan be applied to the segment via the base 23294 and/or the movableportion 23296 wherein the heat and/or the force applied to the segmentcan distort the cover 23226. More specifically, in at least oneembodiment, the movable portion 23296 can define a pocket 23297 whichcan be contoured to apply a clamping force to certain portions of thecover 23226, such as the open ends thereof, in order to close, flatten,and/or neck down such portions of the tissue thickness compensator23220. For instance, the pocket 23297 can be configured to form theclosed ends 23228 of the tissue thickness compensator 23220 and flattenthe portion of the tissue thickness compensator 23220 positionedintermediate the closed ends 23228. After the tissue thicknesscompensator 23220 has been suitably formed, the movable portion 23296can be moved to an open position and the tissue thickness compensator23220 can be removed from the die. In various embodiments, the tissuethickness compensator 23220 can then be positioned in a coolingcontainer wherein the compensator 23220 can be permitted to cool to roomtemperature and/or any other suitable temperature.

In certain alternative embodiments, further to the above, the tube 23227can be positioned within a heat-forming die after the material 23225 hasbeen positioned therein. After the tube 23227, and the material 23225positioned therein, have been formed, the tube 23227 and the material23225 can then be segmented into a plurality of tissue thicknesscompensators 23220, for example. In various embodiments, referring againto FIG. 142, the tissue thickness compensator 23220 can comprise lateralwings, or clips, 23229 which can be configured to be attached to theanvil 22060, for example. In at least one such embodiment, the lateralwings 23229 can be formed in the cover 23226 when the tissue thicknesscompensator 23220 is formed between the die portions 23294 and 23296, asdescribed above. Referring now to FIG. 143, a tissue thicknesscompensator 23320 can comprise lateral wings 23329 extending from cover23326. In certain embodiments, referring now to FIG. 144, a tissuethickness compensator 23420 can comprise a cover 23426 having one ormore lateral flexible joints 23428, for example, which can permit thecover 23426 to flex and flatten when it is subjected to a compressivepressure in the heat-forming die described above. In variousembodiments, as a result of the above, the tissue thickness compensator23220 may not comprise lateral seams. In such embodiments, referringagain to FIG. 142, the material 23225 may extend to the lateral edges ofthe anvil 22060, for example.

As described above, a yarn strand can be pulled through a tube and thencut to length to form one or more tissue thickness compensators. Invarious embodiments, further to the above, a yarn strand can be pulledor pushed through a tube utilizing a rigid strand of material. In atleast one embodiment, a rigid strand of polymer material, such as PCL,for example, can be heated above its glass transition temperature andstretched into a deformed shape. In at least one such embodiment, therigid strand can comprise an undeformed serpentine shape which, whenstretched into its deformed shape, can comprise a straight, or at leastsubstantially straight, shape, for example. Thereafter, the rigid strandcan be cooled below the glass transition temperature of the materialwhile the rigid strand is constrained so that the rigid strand canmaintain its deformed shape. Once the rigid strand is in its deformedshape, in various embodiments, ORC fibers, for example, can be formedaround the rigid strand. In certain embodiments, an ORC yarn strand, forexample, can be wound around, flocked, and/or folded over the rigidstrand. Alternatively, the rigid strand can be inserted into ORC fibers,for example. In certain embodiments, the rigid strand can comprise asticky surface which can be rolled and/or dipped within the ORC fibers.In any event, the rigid strand and the ORC fibers can then be insertedinto a tube, similar to the above, and reheated above the glasstransition temperature of the rigid strand. In such circumstances, therigid strand can be unconstrained, or at least substantiallyunconstrained, and can be permitted to return, or at least substantiallyreturn, to its original undeformed shape. In at least one suchembodiment, the rigid strand can contract when returning to its originalshape and retract the ORC fibers into the tube. In certain embodiments,the center of the tube can be clamped to hold the rigid strand and theORC fibers in the center of the tube as the rigid tube contracts.Similar to the above, the ends of the tube can be sealed to enclose therigid strand and the ORC fibers therein.

In various embodiments, referring now to FIG. 244, a tissue thicknesscompensator 33320 can comprise a shell 33326, a compressible corepositioned within the shell 33326, and closed ends 33328 which can beconfigured to contain the compressible core within the shell 33326. Inat least one embodiment, further to the above, the shell 33326 can beproduced from a continuous extruding process and can comprise acontinuous cross-sectional shape along the length thereof. In certainembodiments, referring now to FIGS. 245-247, a tissue thicknesscompensator 33420 can comprise a shell 33426, a cavity 33424 defined inthe shell 33426, and a core 33425 positioned within the cavity 33424. Inat least one such embodiment, the shell 33426 can comprise a film bodyformed from a continuous extruded shape and the core 33425 can comprisea fibrous medicament core, such as ORC, for example. In at least oneembodiment, the shell 33426 can comprise one or more flexible legs 33423which can be configured to extend into a knife slot 22063 defined in theanvil 22060 and releasably retain the tissue thickness compensator 33420to the anvil 22060. In certain embodiments, referring now to FIGS.248-250, a tissue thickness compensator 33520 can comprise a shell33526, a cavity 33524 defined in the shell 33526, and a core 33425positioned within the cavity 33524. In at least one such embodiment, theshell 33526 can comprise a film body formed from a continuous extrudedshape and the core 33425 can comprise a fibrous medicament core, such asORC, for example. In at least one embodiment, the shell 33526 cancomprise one or more retention members 33528 which can be configured toextend around the outside surface of the anvil 22060 and releasablyretain the tissue thickness compensator 33520 to the anvil 22060. In atleast one such embodiment, referring primarily to FIG. 250, the shell33526 can comprise movable portions 33527 and a gap 33523 definedbetween the movable portions 33527 wherein, after the tissue thicknesscompensator 33520 has detached from the anvil 22060, the movableportions 33527 can spring open to expose the core 33425 containedtherein. In certain embodiments, referring now to FIGS. 251-252, atissue thickness compensator 33620 can comprise a shell 33626, a cavity33424 defined in the shell 33626, and a core 33425 positioned within thecavity 33424. In at least one such embodiment, the shell 33626 cancomprise a film body formed from a continuous extruded shape and thecore 33425 can comprise a fibrous medicament core, such as ORC, forexample. In at least one embodiment, the shell 33626 can comprise a thinsection 33623 which can be aligned with the knife slot 22063 defined inthe anvil 22060 such that a cutting member passing through the tissuethickness compensator 33620 can pass through the thin section 33623 andreduce the force or energy needed to transect the tissue thicknesscompensator 33620. In certain embodiments, referring now to FIGS.253-254, a tissue thickness compensator 33720 can comprise a shell33726, a cavity 33424 defined in the shell 33726, and a core 33425positioned within the cavity 33424. In at least one such embodiment, theshell 33726 can comprise a film body formed from a continuous extrudedshape and the core 33425 can comprise a fibrous medicament core, such asORC, for example. In at least one embodiment, the shell 33726 cancomprise one or more retention members 33723 which can be configured towrap around the outside surface of the anvil 22060 and releasably retainthe tissue thickness compensator 33720 to the anvil 22060. In certainembodiments, referring now to FIGS. 255-256, a tissue thicknesscompensator 33820 can comprise a shell 33826, a cavity 33424 defined inthe shell 33826, and a core 33425 positioned within the cavity 33424. Inat least one such embodiment, the shell 33826 can comprise a film bodyformed from a continuous extruded shape and the core 33425 can comprisea fibrous medicament core, such as ORC, for example. In at least oneembodiment, the shell 33826 can comprise a substantially rectangularcavity 33424 and a substantially flat tissue contacting surface 33829 asopposed to the arcuate cavity 33424 and tissue contacting surfacedepicted in FIG. 254, for example. In certain embodiments, referring nowto FIGS. 257-258, a tissue thickness compensator 33920 can comprise ashell 33926, a plurality of cavities 33924 defined in the shell 33926,and a core 33925 positioned within each of the cavities 33924. In atleast one such embodiment, the shell 33926 can comprise a film bodyformed from a continuous extruded shape and the cores 33925 can eachcomprise a fibrous medicament core, such as ORC, for example. In certainembodiments, the cores 33925 can be comprised of different materials. Inat least one embodiment, the shell 33926 can comprise one or moreretention members 33923 which can be configured to extend into the knifeslot 22063 of the anvil 22060.

Referring now to FIG. 153, a tissue thickness compensator can be formedutilizing a folding process. In various embodiments, a material 23525,such as oxidized regenerated cellulose, for example, can be placed on acover sheet 23526 which can be folded and then sealed in order toencapsulate the material 23525. In at least one such embodiment, thecover sheet 23526 can be comprised of cap gly, for example. In certainembodiments, a continuous process can be utilized in which the coversheet 23526 can be passed under a hopper 23592 which is configured todispense the material 23525 onto the cover sheet 23526. In at least onesuch embodiment, the cover sheet 23526 can be flattened between a roller23591 and an anvil 23590 before the material 23525 is placed onto thecover sheet 23526. In certain embodiments, the material 23525 may beplaced on one side, or half, of the cover sheet 23526 wherein the otherside, or half, of the cover sheet 23526 can be folded, or flipped, overthe material 23525. Before, during, and/or after the material 23525 hasbeen placed on the cover sheet 23526, the cover sheet 23526 can befolded, or at least partially folded. In various embodiments, the anvil23590, for example, can comprise a cam surface 23594 which can beconfigured to lift an edge or side of the longitudinally moving coversheet 23526 and then fold the cover sheet 23526 in half, for example. Inat least one embodiment, the cam surface 23594 can comprise athree-dimensional cam, or barrel cam, which progressively lifts andturns a portion of the cover sheet 23526 as the cover sheet 23526 passesby the cam surface 23594.

After the cover sheet 23526 has been folded over the material 23525, thefolded cover sheet 23526 and the material 23525 positioned therein canpass through a die 23593 which can, in at least one embodiment, compressand/or compact the folded cover sheet 23526 and the material 23525 toform a tube 23527. In certain embodiments, the edges of the folded coversheet 23526 can be sealed closed utilizing any suitable process such asthermal welding and/or laser welding, for example. In variousembodiments, the tube 23527 can be further flattened by one or morerollers 23595, for example, before the sidewall of the tube 23527 hasbeen sealed. In certain embodiments, the tube 23527 can be furtherflattened by one or more rollers after the sidewall of the tube 23527has been sealed. In any event, the tube 23527 can be segmented intoportions to create separate tissue thickness compensators. In variousembodiments, the ends of the tissue thickness compensators can be sealedutilizing any suitable process such as thermal welding and/or laserwelding, for example, while, in other embodiments, one or both of theends of the tissue thickness compensator can remain in an openconfiguration, for example.

In various embodiments, referring now to FIG. 154, a compensator can beattached to an anvil, such as anvil 22060, for example, wherein thecompensator can be configured to store at least one medicament therein.In at least one embodiment, a compensator 23620 can comprise a centralbody portion 23626 and lateral attachment portions 23628 which can beconfigured to be attached to the anvil 22060. In certain embodiments,the compensator 23620 can further comprise an array of capillarychannels 23627 defined in a tissue contacting surface 23625 of thecompensator 23620 wherein the capillary channels 23627 can be configuredto store one or medicaments therein. In at least one such embodiment,the medicament can comprise a fluid which, owing to fluid tensionforces, can be retained between the sidewalls of the capillary channels23627. In various circumstances, the medicament can be applied to thecompensator 23620 before the compensator 23620 is attached to the anvil22060 while, in some circumstances, the medicament can be applied to thecompensator 23620 after it has been attached to the anvil 22060, forexample. In any event, the compensator 23620 can be configured tocontact tissue positioned between the anvil 22060 and a staple cartridgepositioned opposite the anvil 22060 wherein the medicament stored in thecapillary channels 23627 can flow onto the tissue. In variouscircumstances, the medicament can flow within the capillary channels23627.

In various embodiments, referring again to the compensator 23620illustrated in FIG. 154, the array of capillary channels 23627 can beconstructed and arranged in a cross-hatched pattern wherein a firstquantity of channels 23627 can extend in a first direction and a secondquantity of channels 23627 can extend in a second direction. In at leastone embodiment, the first quantity of channels 23627 can intersect andcan be in fluid communication with the second quantity of channels23627. Referring now to FIG. 155, a compensator 23920 can comprise abody 23926 which includes an array of capillary channels 23927 definedin a tissue-contacting surface 23925. In various embodiments, thechannels 23927 can be defined along linear paths while, in certainembodiments, the channels 23927 can be defined along non-linear paths.In at least one embodiment, a first quantity of channels 23927 canextend along axes 23923 while a second quantity of channels 23927 canextend along axes 23924, for example, wherein the axes 23923 can extendin different directions than the axes 23924. In various embodiments, theaxes 23923 can be perpendicular, or at least substantiallyperpendicular, to the axes 23924 wherein, in at least one embodiment,the channels 23627 can define islands 23922 therebetween. In at leastone such embodiment, the top surfaces of the islands 23922 can definethe tissue contacting surface 23925 of the compensator 23920. In variousembodiments, the compensator 23920 can comprise a longitudinal axis23921 and the channels 23627 can extend in directions which aretransverse or skew with respect to the longitudinal axis 23921. Incertain embodiments, referring again to FIG. 154, a compensator 23720can comprise a body 23726 and a plurality of capillary channels 23727defined in the body 23726. In at least one embodiment, the compensator23720 can further comprise a longitudinal channel 23721 which can be influid communication with the capillary channels 23727. In variousembodiments, one or medicaments can be stored in the longitudinalchannel 23721 wherein the medicaments can flow between the channel 23721and the capillary channels 23727, for example. In at least oneembodiment, the channel 23721 can define a longitudinal protrusion whichcan extend upwardly into a longitudinal knife slot 22061 defined in theanvil 22060.

As discussed above, referring again to FIG. 154, an array of capillarychannels defined in a compensator can comprise a cross-hatched pattern.In various other embodiments, however, an array of capillary channelscan comprise any suitable shape or configuration. For example, referringto compensator 23820 illustrated in FIG. 154, the channels 23827 definedin the body 23826 of the compensator 23820 can comprise parallel,diagonal channels which converge toward and/or diverge away from acentral channel 23821, for example. Referring now to FIG. 158, an endeffector of a surgical stapling instrument can include a staplecartridge 24000 including a tissue thickness compensator 24010 wherein,in at least one embodiment, the tissue thickness compensator 24010 caninclude at least one medicament, such as medicament 24001, for example,therein and/or thereon. Referring now to FIG. 159, a compensator 24020attached to an anvil 24060, for example, can be moved into a closedposition in order to place the compensator 24020 in contact with thetissue thickness compensator 24010. In such circumstances, themedicament 24001, for example, can be transferred from the tissuethickness compensator 24010 to the compensator 24020. In at least oneembodiment, referring now to FIG. 160, the compensator 24020 cancomprise a tissue contacting surface 24025 which can be brought intocontact with the tissue thickness compensator 24010 wherein, in certainembodiments, the medicament 24001 can flow into capillary channels 24027defined in the tissue contacting surface 24025. In certain embodiments,referring now to FIG. 157, the compensator 24020 can include at leastone medicament, such as medicament 24002, for example, thereon and/ortherein which can be transferred from the compensator 24020 to thetissue thickness compensator 24010.

In various embodiments, referring now to FIGS. 240 and 241, a tissuethickness compensator 33020 can comprise a plurality of channels and/orwells defined in the surface thereof. In at least one embodiment, thetissue thickness compensator 33020 can comprise a longitudinal channel33026 that extends along a longitudinal axis defined through the tissuethickness compensator 33020. In at least one such embodiment, the end ofthe longitudinal channel 33026 can be in fluid communication with theperimeter of the tissue thickness compensator 33020. The tissuethickness compensator 33020 can further comprise a plurality of wells33022 and, in addition, a plurality of diagonal channels 33024 which arein fluid communication with the wells 33022 and the longitudinal channel33026. In certain embodiments, the tissue thickness compensator 33020can further comprise a plurality of inlet-outlet channels 33027 whichcan be in fluid communication with the wells 33022 and the perimeter ofthe tissue thickness compensator 33020. In various embodiments, as aresult of the above, fluids can flow into and/or out of the tissuethickness compensator 33020 before, during, and/or after it has beenimplanted against a patient's tissue. In certain embodiments, thepattern of channels 33024, 33026, and 33027 and the wells 33022 definedin the tissue-contacting surface 33025 of the tissue thicknesscompensator 33020 can define gripping edges which can be configured tocontact the tissue and limit slipping between the tissue thicknesscompensator 33020 and the tissue. Referring now to the alternativeembodiment illustrated in FIGS. 240A and 241A, a tissue thicknesscompensator 33120 can comprise a plurality of circular channels definedin the surface thereof. In various embodiments, the tissue thicknesscompensator 33120 can comprise concentric circular channels 33127 whichcomprise openings defined in the perimeter of the tissue thicknesscompensator 33120. Similar to the above, fluids can flow into and/or outof the tissue thickness compensator 33120 through the channels 33127. Inat least one embodiment, the tissue thickness compensator 33120 cancomprise concentric circular channels 33122 which may not includeopenings defined in the perimeter of the tissue thickness compensator33120. Referring now to the alternative embodiment illustrated in FIGS.242 and 243, a tissue thickness compensator 33220 can comprise aplurality of ridges 33227 extending therefrom which can be configured togrip tissue that is positioned against the tissue thickness compensator33220. In at least one embodiment, the ridges 33227 can be straightwhile, in some embodiments, the ridges 33227 can comprise a curvedcontour, for example. Although the ridges and channels described abovemay be useful for tissue thickness compensators, in various embodiments,such ridges and channels could be utilized with any suitablebioabsorbable and/or biocompatible layer.

In various embodiments, a compensator can be comprised of a plurality oflayers. In at least one embodiment, the compensator can comprise a firstlayer and a second layer attached to the first layer, for example. Incertain embodiments, the first layer can comprise a tissue contactingsurface and a plurality of capillary channels defined in the tissuecontacting surface. In at least one embodiment, the first layer can alsocomprise capillary channels defined in a side which faces the secondlayer and faces opposite the tissue contacting surface. In certainembodiments, the second layer can comprise capillary channels definedtherein. In at least one embodiment, wells can be defined between thefirst layer and the second layer of the compensator. In variousembodiments, the capillary channels can be formed in the layers of thecompensator utilizing any suitable process, such as during a moldingprocess in which the layers are formed and/or during a heat-stakingprocess, for example. In at least one embodiment, a heat-staking processcan be utilized to attach the layers of the compensator to one another,for example. In at least one such embodiment, the layers can becomprised of a material which can become deformable when heat is appliedthereto, such as CAP/GLY (36/64), for example. In any event, in variousembodiments, the capillary channels defined in the tissue contactingsurface of the compensator can define gripping surfaces therebetweenwhich can improve the grip, or control, that can be applied to tissuepositioned between the anvil and the staple cartridge of the surgicalstapling instrument. Stated another way, the capillary channels definedin the tissue-contacting surface of a compensator can decrease the areain which the compensator can contact the tissue. In such circumstances,the smaller contact area can result in higher contact pressures betweenthe compensator and the tissue for a given force. In variouscircumstances, the higher contact pressures can reduce slipping betweenthe compensator and the tissue.

In various embodiments, one or medicaments can be positioned within thecapillary channels and/or voids defined within and/or between the firstlayer and the second layer. In certain embodiments, the plurality oflayers comprising a compensator can comprise a pack of therapeuticlayers, or therapies. For instance, a first layer can be comprised of afirst medicament and a second layer can be comprised of a secondmedicament, wherein the first medicament can be different than thesecond medicament. In at least one such embodiment, capillary channelsdefined in the first layer can store a third medicament and capillarychannels defined in the second layer can store a fourth medicament,wherein the first, second, third, and/or fourth medicaments can bedifferent, for example. In at least one embodiment, the first, second,third, and/or fourth medicaments can be different, for example. Invarious embodiments, referring now to FIG. 161, a compensator 24120 cancomprise a plurality of layers, such as layers 24121-24125, for example.In at least one embodiment, the first layer 24121 and/or the fifth layer24125 can comprise a flat sheet of material between which the secondlayer 24122, the third layer 24123, and/or the fourth layer 24124 can besandwiched. In various embodiments, one or more of the layers24121-24125 can comprise one or more channels 24127 defined therein. Inat least one embodiment, the channels 24127 can extend from one end ofthe compensator 24120 to the other end and, in certain embodiments, thechannels 24127 can extend between one side of the compensator 24120 tothe other. In certain other embodiments, the channels 24127 can extendin any suitable direction between any suitable sides and/or ends of thecompensator 24120. In various embodiments, referring now to FIGS. 164and 165, a compensator 24820 can comprise two or more inner layers 24827which can define lateral channels 24822, for example, which extend fromone side of the compensator 24820 to the other. In certain embodiments,referring again to FIG. 161, the channels 24127 defined in one of thelayers 24121-24125 can be aligned with the channels defined in a layerpositioned adjacent thereto. In some embodiments, the channels 24127defined in one of the layers 24121-24125 can face, or open toward, aflat surface on a layer positioned adjacent thereto. In variousembodiments, referring again to FIG. 161, one or more of the layers24121-24125 can comprise at least one well 24129 defined therein. In atleast one embodiment, the wells 24129 can be in fluid communication withone or more of the channels 24127 defined in the layer. Similar to theabove, the wells 24129 can comprise an opening which opens toward, orfaces, an adjacent layer wherein the adjacent layer can cover theopening.

In various embodiments, further to the above, the channels 24127 and/orthe wells 24129 can be configured to contain one or medicaments therein.In at least one embodiment, the channels 24127 can comprise one or moreopen ends which can permit a medicament to flow out of the channels24127. Similarly, in at least one embodiment, the channels 24127 caninclude one or more openings which can be configured to permit a fluid,such as blood, for example, to flow into the channels 24127. In suchembodiments, the fluid can flow into the compensator 24120, absorb atleast a portion of a medicament and/or a layer 24121-24125, and thenflow out of the compensator 24120. Referring again to FIGS. 164 and 165,the compensator 24820 can comprise apertures 24828 defined in outerlayers 24826, for example. In various embodiments, referring again toFIG. 161, the layers 24121-24125 can be comprised of any suitablematerial, such as a bioabsorbable polymer, PLA, and/or PGA, for example.In certain embodiments, all of the layers 24121-24125 can be comprisedof the same material. In certain other embodiments, one or more of thelayers 24121-24125 could be comprised of different materials. In variousembodiments, one or more of the layers 24121-24125 can include throughholes 24128 extending therethrough which can be configured to permitfluids, such as blood, for example, to flow into the channels 24127,wells 24126, and/or between two or more of the layers 24121-21135, forexample. In certain embodiments, one or more of the layers 24121-24125can be connected to each other utilizing a heat-welding and/orlaser-welding process, for example. In such embodiments, the fluid, orfluids, flowing into the compensator 24120 can dissolve the weldedportions of the layers 24121-24125 and permit the layers 24121-24125 toseparate and/or delaminate. In certain embodiments, one or more of thelayers 24121-24125 can be comprised of a material which dissolves at afaster rate and/or a slower rate than the material, or materials,comprising the other layers 24121-24125. In at least one suchembodiment, the inner layers 24122-24124 of the compensator 24120 can becomprised of a material which dissolves at a faster rate than thematerial, or materials, which comprise the outer layers 24121 and 24125,for example. In such embodiments, the compensator 24120 can maintain aconsistent, or at least substantially consistent, general shape whilethe interior of the compensator 24120 is dissolved away. In certainother embodiments, the outermost layers of a compensator can becomprised of a material which dissolves at a faster rate than thematerial, or materials, which comprise the innermost layers of thecompensator, for example. In various embodiments, the layers cancomprise sheets of material having a thickness between approximately 1mil and approximately 4 mils, for example.

In various embodiments, referring now to FIGS. 162 and 163, acompensator, such as compensator 24220, for example, can comprise asupport layer 24226 which can be configured to be attached to an anvil,such as anvil 22060, for example, and/or a staple cartridge. In certainembodiments, the compensator 24220 can further comprise a scaffold 24222attached to the support layer 24226 wherein the scaffold 24222 cancomprise a plurality of scaffold layers 24227. In at least oneembodiment, the scaffold can comprise a three-dimensional structuralmatrix, for example. In various embodiments, each of the scaffold layers24227 can be comprised of a plurality of fibers. In at least oneembodiment, referring now to FIG. 166, each scaffold layer 24227 can becomprised of a fiber weave including a first plurality of fibers 24228extending in a first direction and a second plurality of fibers 24229extending in a second, or different, direction. In certain embodiments,each fiber weave can comprise a plurality of pockets, or cavities, 24223wherein the layers 24227, the fibers 24228, 24229, and the cavities24223 can define a matrix favorable to tissue and cellular ingrowth. Invarious embodiments, the fibers 24228, 24229, and/or any other suitablefibers, can be comprised of a bioabsorbable material. In at least oneembodiment, the fibers can be comprised of a haemostatic agent, boundactive agents such as those that are biologically and/orpharmacologically active, and/or support members, for example, which canbe interweaved with one another. In any event, the material of thefibers can be selected to induce a desirable biologic response such ascellular migration into the scaffold 24222, ECM secretion, and/or theproliferation of structural support cells, for example.

In various embodiments, further to the above, the support layer 24226can be configured to structurally support the scaffold 24222. In atleast one embodiment, the scaffold 24222 can be attached to the supportlayer 24226 utilizing one or more bioabsorbable adhesives, for example.Similarly, in certain embodiments, the support layer 24226 can beattached to an anvil or a staple cartridge utilizing one or morebiocompatible adhesives, for example. In various embodiments, the layers24227 of the scaffold 24222 can be arranged, or stacked, in any suitablemanner. In certain embodiments, each layer 24227 can comprise a patternof fibers wherein the layers 24227 can be arranged in the scaffold 24222such that the patterns of the layers 24227 are aligned with each other.In at least one embodiment, referring to FIG. 167, the layers 24227 canbe stacked on one another such that the fibers 24228 in a first layer24227 are aligned with the fibers 24228 in a second layer 24227.Likewise, the layers 24227 can be stacked on one another such that thefibers 24229 in the first layer 24227 are aligned with the fibers 24229in the second layer 24227. In certain embodiments, referring now to FIG.168, a scaffold 24422 can comprise a plurality of scaffold layers 24427wherein the fibers 24429 in each scaffold layer 24427 are oriented inthe same direction, such as a longitudinal direction, for example. Incertain embodiments, referring now to FIG. 170, each scaffold layer24227 can comprise a pattern of fibers wherein the layers 24227 can bearranged in a scaffold 24322 such that the patterns of the layers 24227are not aligned with each other. In at least one embodiment, the layers24227 can be stacked on one another such that the fibers 24228 in afirst layer 24227 extend in a direction which is transverse to oroblique with the fibers 24228 in a second layer 24227. Likewise, thelayers 24227 can be stacked on one another such that the fibers 24229 inthe first layer 24227 extend in a direction which is transverse to oroblique with the fibers 24229 in the second layer 24227. In certainembodiments, referring now to FIG. 171, a scaffold 24522 can comprise aplurality of scaffold layers 24427 which are oriented such that thefibers 24229 in each scaffold layer 24427 are oriented in differentdirections, for example.

In various embodiments, further to the above, a first scaffold layer24227 of a scaffold 24222, for example, can be comprised of a firstmaterial while a second scaffold layer 24227 of the scaffold 24222 canbe comprised of a second, or different, material. In at least oneembodiment, the first material can comprise a first medicament while thesecond material can comprise a second, or different, medicament, forexample. In various embodiments, further to the above, a first scaffoldlayer 24227 of a scaffold 24222, for example, can comprise a firstmedicament absorbed into the fibers thereof while a second scaffoldlayer 24227 of the scaffold 24222 can comprise a second, or different,medicament absorbed into the fibers thereof, for example. In at leastone embodiment, the first material can comprise a first medicament whilethe second material can comprise a second, or different, medicament, forexample. In certain embodiments, a scaffold can comprise any suitablenumber of layers having any suitable density of fibers which arecomprised of any suitable number of materials.

Tissue thickness compensators may be installed in a surgical device,such as a surgical cutting and stapling device, for example, utilizing aretainer. The retainer can include a gripping surface and enable asurgeon, nurse, technician, or other person to align one or more of thetissue thickness compensators with features of the surgical instrument,such as an anvil and/or a staple cartridge, for example. In variousembodiments, the retainer may include features that align the one ormore tissue thickness compensators by engaging a staple cartridge of thesurgical instrument. In certain embodiments, the retainer may includefeatures that align one or more tissue thickness compensators byengaging an anvil of a surgical instrument. In certain embodiments, astaple cartridge for the surgical instrument may be included with theretainer and engaging the retainer with the surgical instrument caninstall the staple cartridge in the surgical instrument and align one ormore of the tissue thickness compensators. After the tissue thicknesscompensators have been aligned with and attached to the surgicalinstrument, the retainer may be detached from the tissue thicknesscompensators and then removed from the surgical instrument.

FIGS. 61-67 illustrate an embodiment of a retainer 19000 that may beused to attach a first tissue thickness compensator 19002 to an anvil19040 and a second tissue thickness compensator 19004 to a staplecartridge 19050 of a surgical stapler, for example. A retainer assembly19060 can be provided which includes the retainer 19000, the firsttissue thickness compensator 19002, and the second tissue thicknesscompensator 19004. In use, generally, the retainer assembly 19060 may beinserted between the anvil 19040 and a channel configured to support thestaple cartridge 19050. Thereafter, the anvil 19040 can be closed. Byclosing the anvil 19040, the anvil 19040 can push downwardly onto thefirst tissue thickness compensator 19002 such that the first tissuethickness compensator 19002 may be attached to the anvil 19040. In atleast one embodiment, closing the anvil 19040 pushes downwardly on theretainer 19000 and seats the staple cartridge 19050 into the channel ofthe surgical instrument. When the anvil 19040 is reopened, the firsttissue thickness compensator 19002 can detach from the retainer 19000and when the retainer 19000 is subsequently removed from the surgicaldevice, the retainer 19000 can detach from the second tissue thicknesscompensator 19004. The surgical device is then ready for use with thefirst tissue thickness compensator 19002 attached to the anvil 19040 andthe second tissue thickness compensator 19004 attached to the staplecartridge 19050.

Referring to FIG. 61, the retainer 19000 may include a grip 19014 bywhich a person, such as a surgeon, nurse, or technician preparingsurgical instruments may grasp the retainer 19000. The retainer 19000may include a first surface 19001 on which a first tissue thicknesscompensator 19002 may be positioned and an opposing second surface 19003on which a second tissue thickness compensator 19004 may be positioned.In various embodiments, one or more adhesives can be applied to thefirst surface 19001 and/or the second surface 19003 for attaching thefirst and second tissue thickness compensators 19002 and 19004 thereto.The retainer 19000 also may include clips that can engage a staplecartridge 19050 of the surgical device, for example. In at least oneembodiment, referring to FIG. 64, the retainer 19000 may include distalclips 19108 configured to engage a recess 19056 at a distal end of thestaple cartridge 19050 and/or proximal clips 19106 configured engage aridge or edge 19054 on the staple cartridge 19050.

Referring to FIG. 61, in various embodiments, the first tissue thicknesscompensator 19002 may include a retainer-facing surface 19006 and ananvil-facing surface 19010. The retainer-facing surface 19006 can beattached to the first surface 19001 of the retainer 19000 by adhesivesand/or engagement features, for example. The anvil-facing surface 19010may include at least one adhesive thereon which can attach the firsttissue thickness compensator 19002 to the anvil 19040 of the surgicaldevice. For example, the adhesive can comprise an activatable adhesivethat may adhere to a staple forming surface 19044 (FIG. 63) of the anvil19040.

Referring to FIGS. 61 and 63-66, the anvil-facing surface 19010 of thefirst tissue thickness compensator may include engagement features 19020that engage similar engagement features 19042 on the anvil 19040. Thus,in various embodiments, a first retention force can retain the firsttissue thickness compensator 19002 to the retainer 19000 and a secondretention force can retain the first tissue thickness compensator 19002to the anvil 19040. In various embodiments, the second retention forcecan be greater than the first retention force such that the first tissuethickness compensator 19002 can remain attached to the anvil 19040 andseparate from the retainer 19000 when the retainer 19000 is removed fromthe end effector.

Referring again to FIG. 61, the second tissue thickness compensator19004 may include a retainer-facing surface 19008 and astaple-cartridge-facing surface 19012. The retainer-facing surface 19006can be attached to the first surface 19001 of the retainer 19000 by oneor more adhesives and/or engagement features. Thestaple-cartridge-facing surface 19012 may include an adhesive thereonwhich can attach the second tissue thickness compensator 19004 to thestaple cartridge 19050 of the surgical device. For example, referring toFIG. 64, the adhesive may adhere the second tissue thickness compensator19004 to a staple deck 19052 of the staple cartridge 19050. Thestaple-cartridge-facing surface 19012 also may include engagementfeatures that engage co-operating engagement features on the staplecartridge 19050. Thus, in various embodiments, a first retention forcecan retain the second tissue thickness compensator 19004 to the retainer19000 and a second retention force can retain the second tissuethickness compensator 19004 to the staple cartridge 19050. In variousembodiments, the second retention force can be greater than the firstretention force such that the second tissue thickness compensator 19004can remain attached to the staple cartridge 19050 and separate from theretainer 19000 when the retainer 19000 is removed from the end effector.

As shown in FIG. 64, the retainer assembly 19060 may be attached to astaple cartridge 19050 as indicated by arrow A. As described above,distal clips 19018 on the retainer 19000 may engage a recess 19056 inthe staple cartridge and proximal clips 19016 on the retainer may engagethe edge or ridge 19054 on the staple cartridge 19050. At such point,the retainer 19000 is attached to the staple cartridge 19050, as shownin FIG. 65, and the second tissue thickness compensator 19004 can beattached to the staple cartridge 19050. As shown in FIG. 66, closure ofthe anvil 19040 of the surgical device in the direction of arrow B maybring a surface 19044 of the anvil, such as a staple-forming surfaceand/or a tissue contacting surface, for example, into contact with thefirst tissue thickness compensator 19002. As described above, the anvil19040 contacting the first tissue thickness compensator 19002 can causethe first tissue thickness compensator 19002 to become attached to theanvil 19040.

After the retainer assembly 19060 has been attached to the staplecartridge 19050 and the anvil 19040 has been closed, the first tissuethickness compensator 19002 can be attached to the anvil 19040 and thesecond tissue thickness compensator 19004 can be attached to the staplecartridge 19050. As described above, the retention force retaining thefirst tissue thickness compensator 19002 to the retainer 19000 can beless than the retention force holding the first tissue thicknesscompensator 19002 to the anvil 19040. Thus, when the anvil 19040 isreopened, the first tissue thickness compensator 19002 can detach fromthe retainer 19000 and remain with the anvil 19040, as shown in FIG. 67.As also described above, the retention force retaining the second tissuethickness compensator 19004 to the retainer 19000 can be less than theretention force holding the first tissue thickness compensator 19004 tothe staple cartridge 19050. Thus, when the retainer 19000 is removed inthe directions of arrows C and D in FIG. 67, the retainer 19000 candetach from the second tissue thickness compensator 19004. The surgicalstapler shown in FIG. 67 includes the first tissue thickness compensator19002 attached to the anvil 19040 and the second tissue thicknesscompensator 19004 attached to the staple cartridge 19050 and is readyfor use.

FIGS. 390-396 show the retainer 19000 being used with a first tissuethickness compensator 19002 and a second tissue thickness compensator19004. In various embodiments, the retainer 19000 may also be used withonly one of the first tissue thickness compensator 19002 and the secondtissue thickness compensator 19004. For example, the first tissuethickness compensator 19002 may be omitted.

FIGS. 68-70 show an embodiment of a retainer 19100 that can includeengagement features 19108 on a surface 19101. As shown in FIGS. 69 and70, the engagement features 19108 on the retainer 19100 engageco-operating engagement features 19109 on a first tissue thicknesscompensator 19102.

FIGS. 71 and 72 show an embodiment of a retainer 19200 that may includea surface 19202 configured to align and attach a tissue thicknesscompensator 19210 to an anvil 19230. The retainer 19200 may includealignment pegs 19204 extending from the surface 19202. The retainer19200 shown in FIGS. 71 and 72 includes four alignment pegs 19204, butmore or fewer alignment pegs 19204 may be present. Referring to FIG. 72,the tissue thickness compensator 19210 can include a body 19212 thatincludes holes 19216 that can be located such that they that correspondto the locations of the alignment pegs 19204 extending from the retainer19200. Each hole 19216 in the tissue thickness compensator 19210 fitsover an alignment peg 19204, and owing to a close fit between the holes19216 and the pegs 19204, the tissue thickness compensator 19210 can bealigned with the retainer 19200. In various embodiments, each hole 19216may be slightly smaller than its corresponding peg 19204 such that eachhole 19216 stretches when placed on its peg 19204. Such stretching canhold the holes 19216 on the pegs 19204. In certain embodiments, eachhole 19216 may include an adhesive therein to create a releasable bondbetween the pegs 19204 and the tissue thickness compensator 19210.

The tissue thickness compensator 19220 may include tabs 19220 extendingfrom a body 19212 of the tissue thickness compensator 19220 which can beconfigured to be received by slots 19234 in an anvil 19230. In variousembodiments, the slots 19234 in the anvil 19230 may be located in astaple forming surface 19232, for example. After the retainer 19200 hasbeen attached to a staple cartridge, similar to the embodimentsdescribed above, the anvil 19230 can be closed against the tissuethickness compensator 19210 on the retainer 19200. As the anvil 19230 isclosed, referring to FIG. 72, the tabs 19220 on the tissue thicknesscompensator 19210 can engage the slots 19234, thereby attaching thetissue thickness compensator 19210 to the anvil 19230. Referringprimarily to FIG. 71, each tab 19220 may include a tapered portion 19222that guides the tab 19220 into the slots 19234 of the anvil 19230. Thetapered portion 19222 can include sloped walls and may increase incross-sectional area along the length thereof. A base portion 19226 ofeach tab 19220 may have a smaller cross-sectional area than the largestcross-sectional area of the tapered portion 19222. In variousembodiments, the tapered portion 19222 may comprise a lock surface 19224wherein, when a tab 19220 enters a slot 19234, the lock surface 19224can catch on a lip 19235 in the slot 19234. As a result, the locksurface 19224 can hold the tab 19220 within the slot 19234 and therebyhold the tissue thickness compensator 19210 to the anvil 19230. Slots19228 defined in the tissue thickness compensator 19210 and extendingbetween the tabs 19220 can enable the tabs 19220 to flex inwardly andfit within the slots 19234. In various embodiments, the tabs 19220 beingheld with the slots 19234 can define a first retention force thatretains the tissue thickness compensator 19210 to the anvil 19230 andthe holes 19216 in the tissue thickness compensator 19210 being held onthe pegs 19204 can define a second retention force. In variousembodiments, the first retention force can be greater than the secondretention force such that the tissue thickness compensator 19210 canremain attached to the anvil 19230 and separate from the retainer 19200when the retainer 19200 is removed from the end effector.

The body 19212 of the tissue thickness compensator 19210 in FIGS. 71 and72 also may define slots 19214 therewithin. The slots 19214 may bealigned along a longitudinal axis of the tissue thickness compensator19210. For example, the slots 19214 may be arranged on a longitudinalaxis such that the slots 19214 are aligned with a longitudinal path of acutting blade of the surgical device when the tissue thicknesscompensator 19210 is attached to an anvil 19230. The slots 19214 mayreduce the amount of energy required by the cutting blade to cut throughthe tissue thickness compensator 19210.

FIGS. 73-83 show an embodiment of a retainer 19300 that includes clips19310 which are configured to retain a tissue thickness compensator19340 on a first surface 19302 of the retainer 19300. When an anvil19360 is closed on the retainer 19300, similar to the above, the anvil19360 can push and displace the clips 19310 outwardly and, as a result,disengage the retainer 19300 from the tissue thickness compensator19340. In various embodiments, the tissue thickness compensator 19340can attach to the anvil 19360 when the anvil 19360 is pressed againstthe tissue thickness compensator 19340 and moved away from the retainer19300 when the anvil 19360 is reopened.

The retainer 19300 may include staple cartridge mounting clips 19312 and19314 which can be similar to those described above with respect toFIGS. 61-70. In addition to the first surface 19302 described above, theretainer 19300 also may include a second surface 19304 that may beconfigured to carry a second tissue thickness compensator. In variousembodiments, the second surface 19304 may include an alignment feature,such as, for example, a raised ridge 19308. The raised ridge 19308 mayengage a slot in a second tissue thickness compensator and/or a slot ina staple cartridge 19370, for example.

Referring to FIGS. 75-77, in use, the retainer 19300 may be attached toa staple cartridge 19370 by clips 19314 and 19312. The first tissuethickness compensator 19340 can be positioned on the first surface 19302at the retainer 19300 and can be held in place by clips 19310. Referringprimarily to FIGS. 81-83, each clip includes a flat 19313 that can clampthe first tissue thickness compensator 19340 against the first surface19302 of the retainer 19300. Each clip 19310 can include aninward-facing tapered or curved surface 19311. As the anvil 19360 movesin the direction of arrow E, referring to FIG. 82, edges 19366 of theanvil 19360 can contact the inward-facing curved surfaces 19311 of theclips 19310. As the anvil 19360 continues to move in the direction ofarrow E, interference between the edges 19366 of the anvil 19360 and thecurved surfaces 19311 of the clips 19310 can push the clips 19310outwardly in the direction of arrow F, as illustrated in FIG. 82. As theclips 19310 move in the direction of arrow F, the first tissue thicknesscompensator 19340 is freed from the flats 19313 of the clips 19310.

As the anvil 19360 continues to move in the direction of arrow E, italso contacts and attaches to the tissue thickness compensator 19340.For example, as the anvil 19360 moves in the direction of arrow E, anengagement feature, such as, for example, a raised ridge 19344, on thetissue thickness compensator 19340 engages a channel 19364 in the anvil19360. The raised ridge 19344 may be configured to have an interferencefit with the channel 19364 such that the tissue thickness compensator19340 becomes attached to the anvil 19360. The tissue thicknesscompensator 19340 may include an adhesive that adheres to surfaces ofthe anvil 19360. In at least one embodiment, the raised ridge 19344 mayinclude an adhesive that adheres to surfaces of the channel 19364.Likewise, surfaces of the body 19342 of the tissue thickness compensator19340 may include an adhesive that adheres to a surface 19362 of theanvil 19360. After the tissue thickness compensator 19340 is attached tothe anvil 19360, the tissue thickness compensator 19340 can lift fromthe retainer 19300 and remain with the anvil 19360 as the anvil 19360returns to its open position by moving in the direction of arrow G, asillustrated in FIG. 83.

FIG. 84 shows a cross-sectional side view of an embodiment of a retainer19400. A first tissue thickness compensator 19410 is positioned on afirst side 19402 of the retainer 19400 and a second tissue thicknesscompensator 19420 is positioned on an opposing second side 19404 of theretainer 19400. The retainer 19400 defines one or more holes 19406extending therethrough. The first tissue thickness compensator 19410 andthe second tissue thickness compensator 19420 are connected through theholes by connectors 19430 which extend through the holes 19406. Invarious embodiments, the first tissue thickness compensator 19410, thesecond tissue thickness compensator 19420, and the connectors 19430 allmay be formed of a unitary material. For example, the first tissuethickness compensator 19410, the second tissue thickness compensator19420, and the connectors 19430 may be overmolded onto the retainer19400. In various other embodiments, the connectors 19430 may be formedas part of one of the tissue thickness compensators, such as, forexample, the first tissue thickness compensator 19410. The connectors19430 may be passed through the holes 19406 and then attached to theremaining tissue thickness compensator, such as, for example, the secondtissue thickness compensator 19420. The connectors 19430 may be attachedto the second tissue thickness compensator 19420, for example, by usingan adhesive or by using an interference fit between an end of theconnector and a receiving port (not shown) in the second tissuethickness compensator 19420. In various embodiments, the connectors19430 may be separate components that are placed into the holes 19406and to which the first tissue thickness compensator 19410 and the secondtissue thickness compensator 19410 may be attached, for example, byusing adhesives or interference fits between ends of the connectors19430 and receiving ports in the first tissue thickness compensator19410 and the second tissue thickness compensator 19420.

After the retainer 19400 has been placed on a staple cartridge 19450,for example, an anvil 19440 of the surgical device can be moved in thedirection of arrow H into a closed position. An adhesive and/orengagement features on a surface 19414 of the first tissue thicknesscompensator 19410 can attach the first tissue thickness compensator19410 to the anvil 19440 when the anvil 19440 closes. Likewise, anadhesive and/or engagement features on a surface 19424 of the secondtissue thickness compensator 19420 can attach the second tissuethickness compensator 19420 to the staple cartridge 19450. After theanvil 19440 is closed and the first and second tissue thicknesscompensators 19410 and 19420 are attached to the anvil 19440 and staplecartridge 19450, respectively, the retainer 19400 may be pulled in thedirection of arrow I (FIG. 88) to remove the retainer 19400 from betweenthe first tissue thickness compensator 19410 and the second tissuethickness compensator 19420 and to break the connectors 19430. As shownin FIG. 89, after the connectors 19430 are broken and the retainer 19400has been removed, the anvil 19440 may be reopened, and the first tissuethickness compensator 19410 will be attached to the anvil 19440 and thesecond tissue thickness compensator 19420 will be attached to the staplecartridge 19450.

In various embodiments, a proximal portion 19407 of each hole 19406 inthe retainer 19400 may include a cutting edge. When the retainer ispulled in the direction of arrow I (FIG. 88), a pulling force istransmitted through the proximal portion 19407 of the holes 19406 tobreak the connectors. A cutting edge at the proximal portion 19407 ofeach hole 19406 will concentrate the transmitted force on a relativelysmall area of each connector. As a result, the connectors will breakmore easily and a lower pulling force may be required to remove theretainer 19400 from between the first tissue thickness compensator 19410and the second tissue thickness compensator 19420.

As described above, a retainer assembly can comprise a retainerpositioned between a first tissue thickness compensator and a secondtissue thickness compensator wherein, after the two tissue thicknesscompensators have been inserted into and attached to an end effector ofa surgical instrument, the retainer can be pulled from between thetissue thickness compensators and removed from the end effector. Incertain embodiments, the retainer can provide a barrier between thefirst and second tissue thickness compensators. Once the retainer isremoved from between the first and second tissue thickness compensators,substances in and/or on the first tissue thickness compensator can reactwith substances in and/or on the second tissue thickness compensator,for example. In some embodiments, one or both of the tissue thicknesscompensators can include a film that can encase substances within thetissue thickness compensators. In certain embodiments, the films can beattached to the retainer wherein, when the retainer is pulled frombetween the tissue thickness compensators, as described above, theretainer can pull the films away from the tissue thickness compensatorsto expose the substances contained therein. At such point, thesubstances within each of the tissue thickness compensators can interactwith each other.

FIGS. 90-100 illustrate an embodiment of a retainer that engages ananvil of a surgical device, such as, for example, a surgical stapler.The retainer may align a first tissue thickness compensator with theanvil and a second tissue thickness compensator with a staple cartridge.Closing the anvil causes the first tissue thickness compensator toattach to the anvil and the second tissue thickness compensator toattach to the staple cartridge. The retainer also may carry the staplecartridge with a tissue thickness compensator optionally disposedbetween the retainer and the staple cartridge. Closing the anvil causesthe staple cartridge to attach to a channel of the surgical stapler andcauses the first tissue thickness compensator to attach to the anvil.

FIGS. 90-93 show an embodiment of a retainer 19500. The retainer 19500includes a grip 19502 by which a surgeon, nurse, technician, or otherperson may manipulate the retainer 19500. The grip 19502 may include atextured surface, such as raised portions 19503, for example, which mayprovide a better gripping surface. In various embodiments, the retainer19500 can include a surface 19504 on which a tissue thicknesscompensator may be mounted. The surface 19504 may include one or moreprojections 19506 wherein the projections 19506 may engage recesses inthe tissue thickness compensator and align the tissue thicknesscompensator relative to the surface 19504 of the retainer 19500. Therecesses in the tissue thickness compensator may be slightly smallerthan the projections 19506 such that, when engaged with the recesses,the projections 19506 can hold the tissue thickness compensator to thesurface 19504. In various embodiments, the projections 19506 may passthrough holes in the tissue thickness compensator and engage a slot,such as, for example, a cutting blade slot 19558 in anvil 19550 shown inFIG. 95, thereby aligning the tissue thickness compensator with theretainer 19500 and also providing additional alignment of the retainer19500 with the anvil 19550. The tissue thickness compensator 19540 mayinclude an adhesive and/or engagement features, described above, on asurface 19542 for attaching the tissue thickness compensator to an anvil19550.

As shown in FIG. 94, in various embodiments, a staple cartridge 19530may be attached to the retainer 19500. The staple cartridge 19530 can beattached to the retainer 19500 by clips 19510 and 19512 extending fromthe retainer 19500. Clips 19512 on the retainer 19500 can engage a slot19534 in the staple cartridge 19530. Clips 19510 of the retainer 19500can surround the bottom 19532 of the staple cartridge 19532. In variousembodiments, a second tissue thickness compensator may be attached tothe staple cartridge 19530. In at least one embodiment, a second tissuethickness compensator may be attached to a staple deck 19536 of thestaple cartridge 19530.

As shown in FIGS. 95 and 96, a retainer assembly 19590 comprising theretainer 19500, a tissue thickness compensator 19540, and a staplecartridge 19530, can slide onto the anvil 19550 of a surgical device,such as a surgical stapler, in the direction of arrow L. The guide tabs19508 on the retainer 19500 can surround edges 19552 of the anvil 19550and position the retainer assembly 19590 relative to the anvil 19550.After the retainer assembly 19590 is engaged on the anvil 19550, asshown in FIGS. 97 and 98, the anvil can be closed in the direction ofarrow M. Closure of the anvil 19550 can position the staple cartridge19530 in a channel 19560 of the surgical device. In at least oneembodiment, closure of the anvil 19550 can cause the clips 19510extending from the retainer 19500 to engage a ridge 19562 of the channel19560 in order to securely position the staple cartridge 19530 in thechannel 19560. When the anvil 19550 is reopened in the direction ofarrow N, referring now to FIGS. 99 and 100, the tissue thicknesscompensator 19540 can remain attached to the anvil 19550 and separatesfrom the retainer 19500. The retainer 19500 then can be removed from thesurgical instrument in the direction of arrow O (FIGS. 99 and 100)leaving the staple cartridge 19530 in the channel 19560 of the surgicaldevice and a tissue thickness compensator 19540 attached to the anvil19550.

FIGS. 101 and 102 show examples of two alternative embodiments of tissuethickness compensators 19570 and 19580, respectively. FIG. 101 is across-sectional view of a tissue thickness compensator 19570 attached toa retainer 19501 wherein the tissue thickness compensator 19570 caninclude protrusions 19574 which can contact edges 19552 of the anvil19550 and partially surround an exterior surface 19556 of the anvil19550. In various embodiments, the protrusions can grip the anvil 19550and/or be attached to the anvil 19550 utilizing one or more adhesives.In order to release the tissue thickness compensator 19570 from theanvil 19550 after the compensator 19570 has been implanted against apatient's tissue, the protrusions 19574 can flex outwardly from theanvil 19550 thereby enabling the tissue thickness compensator 19570 tobe pulled away from the anvil 19550. FIG. 102 is a cross-sectional viewof a tissue thickness compensator 19580 attached to the retainer 19501shown in FIG. 101. The tissue thickness compensator 19580 includes asock 19584 that can surround the anvil 19550 to align the tissuethickness compensator 19580 with the anvil 19550 and/or to retain thetissue thickness compensator 19580 on the anvil 19550. In variousembodiments, the sock 19584 can retain the tissue thickness compensator19580 on the anvil 19550. In order to detach the sock 19584 from theanvil 19550, in various embodiments, the tissue thickness compensator19580 can tear away from the sock 19584 at perforations 19586, forexample. Thus, the sock 19584 can remain on the anvil 19550 while theremainder of the tissue thickness compensator 19580 can remain stapledto the patient tissue.

In certain embodiments, a tissue thickness compensator, such as tissuethickness compensator 19570, for example, can include an interiorportion that comprises a biocompatible substance positioned therein. Invarious embodiments, the biocompatible substance can include ananti-inflammatory, a coagulant, and/or an antibiotic, for example. Invarious embodiments, a body, such as a wafer, for example can beinserted into the interior portion within the tissue thicknesscompensator. In at least one such embodiment, the wafer may be insertedthrough an open end of the tissue thickness compensator into a cavitydefined therein. In certain embodiments, the wafer may be held withinthe cavity of the tissue thickness compensator by an interference fit.In certain embodiments, steps for assembling the wafer into the tissuethickness compensator can include a first step of heating the tissuethickness compensator such that the tissue thickness compensatorexpands. When the tissue thickness compensator expands, in variousembodiments, the cavity defined therein can also expand. When the tissuethickness compensator is in an expanded state, according to a secondstep, the wafer may be inserted into the cavity. Then, as the tissuethickness compensator cools, according to a third step, the cavity canshrink onto the wafer and hold the wafer in place within the cavity.

FIGS. 103-115 illustrate an embodiment of a retainer comprising aseparate insertion tool. The insertion tool can be used to insert anassembly into a surgical instrument, such as a surgical stapler, forexample. The insertion tool can also press a staple cartridge and one ormore tissue thickness compensators of the retainer assembly intoposition within the surgical instrument. Referring to FIGS. 103 and 104,a retainer 19600 may include a first plate 19620 and a second plate19622. The first plate 19620 and the second plate 19622 may be connectedby a hinge 19612. The hinge 19612 can position the first plate 19620 atan angle relative to the second plate 19622 and can also enable thefirst plate 19620 to rotate relative to the second plate 19622 about thehinge 19612.

In various embodiments, the first plate 19620 can include anoutward-facing surface 19604 and an inward-facing surface 19606.Likewise, the second plate 19622 may include an outward-facing surface19610 and an inward-facing surface 19608. In at least one embodiment,the inward-facing surface 19606 of the first plate 19620 may include acam protrusion 19614. Similarly, the inward-facing surface 19608 of thesecond plate 19622 may include a cam protrusion 19616. Referring toFIGS. 110-115, outward-facing surface 19604 of the first plate mayinclude a tissue thickness compensator positioned thereon.Outward-facing surface 19601 of the second plate 19622 may also includea tissue thickness compensator positioned thereon. The tissue thicknesscompensators may be attached to the outer surfaces 19604 and 19610 usingadhesives, engagement features, and/or other suitable attachment means,for example. In various embodiments, the retainer 19600 can includeclips 19618 extending from the second plate 19622 which can beconfigured to engage a staple cartridge 19690, as shown in FIGS. 110 and112-115.

Referring now to FIGS. 105-109, an insertion tool 19630 can include afirst end 19632 and a second end 19634. The first end 19632 can be largeenough to be gripped by a surgeon, nurse, and/or technician, forexample. In various embodiments, the second end 19634 defines a cavity19640 wherein the cavity can include a cam 19648 positioned therein. Afirst side of the cam 19648 may include a first lobe 19642, a secondlobe 19644, and a first anti-lobe 19646 positioned therebetween. Asecond side of the cam 19648 can include a third lobe 19643, a fourthlobe 19645, and a second anti-lobe 19647 positioned therebetween. In atleast one such embodiment, the lobes and the anti-lobes can be arrangedin a mirror-image manner. In other words, the first lobe 19642 may bearranged on the first side of the cam 19648 directly opposite the thirdlobe 19643 on the second side of the cam 19648. Likewise, the secondlobe 19644 may be arranged on the first side of the cam 19648 directlyopposite the fourth lobe 19645 on the second side of the cam 19648.Further, the first anti-lobe 19464 may be arranged on the first side ofthe cam 19648 directly opposite the second anti-lobe 19647 on the secondside of the cam 19648.

In use, the second end 19634 of the insertion tool 19630 is placedbetween the first plate 19620 and the second plate 19622 of the retainer19600 such that the cam protrusion 19614 on the first plate 19620 isengaged with anti-lobe 19646 and cam protrusion 19616 on the secondplate 19622 is engaged with anti-lobe 19647, for example. As shown inFIGS. 112 and 113, an insertion assembly 19700, which includes theretainer 19600, the insertion tool 19630, one or more tissue thicknesscompensators, and staple cartridge 19690 can be inserted into a surgicalinstrument. The surgical instrument, such as a surgical stapler, mayinclude a channel 19740, which is configured to receive the staplecartridge 19690, and an anvil 19720. The insertion assembly 19700 can beinserted into the surgical instrument in the direction of arrow P (FIG.113) to lock the staple cartridge 19690 into the channel 19740. In sucha position, the cams 19614 and 19616 can be aligned with the anti-lobes19646 and 19647, respectively.

After the staple cartridge 19690 is locked into the channel 19740, asshown in FIG. 114, the insertion tool 19600 can continue to be moved inthe direction of arrow Q relative to the surgical instrument. Furthermovement of the insertion tool 19600 in the direction of arrow Q canalign the first lobe 19642 with the first cam protrusion 19614 and thethird lobe 19634 with the second cam protrusion 19616. Such an alignmentcan cause the retainer plates 19620 and 19622 to rotate away from eachother about the hinge 19612 in the direction of arrow R (FIG. 114). Insuch circumstances, the retainer plate 19620 and the tissue thicknesscompensator 19670 can move toward the anvil 19720 and the retainer plate19622 can move toward and contact the anvil 19720. In variousembodiments, as a result of the above, the tissue thickness compensator19670 can be seated on the anvil 19720. After the tissue thicknesscompensator 19670 is attached to the anvil 19720, the insertion tool19630 may be retracted or moved in the direction of arrow S (shown inFIG. 115). Movement of the insertion tool 19630 in the direction ofarrow S can causes the cam protrusions 19614 an 19616 to disengage fromthe first lobe 19642 and the third lobe 19643, respectively, and becomere-aligned with the first anti-lobe 19646 and the second anti-lobe19647, respectively. In various embodiments, the second lobe 19642 andthe fourth lobe 19645 can abut the cam protrusions 19614 and 19616,respectively, and, in at least one embodiment, can prevent the insertiontool 19630 from completely separating from the retainer 19600. With thecam protrusions 19614 and 19616 realigned with the anti-lobes 19646 and19647, the first plate 19620 can at least partially rotate toward thesecond plate 19622 about the hinge 19612 and away from the anvil 19720.The retainer 19600 can also be detached from the channel 19740, invarious embodiments, and then removed in the direction of arrow Sleaving the tissue thickness compensator 19670 attached to the anvil19720, for example.

In the embodiments described herein, a retainer assembly can be utilizedto install one or more tissue thickness compensators into an endeffector of a surgical stapling instrument. In certain embodiments, aretainer assembly can install layers besides tissue thicknesscompensators into a surgical instrument. In at least one embodiment, thelayers may include an absorbable material and/or a biocompatiblematerial, for example.

Referring to FIG. 172, an end effector 12 can be configured to receivean end effector insert 25002. In various embodiments, the end effector12 can comprise a lower jaw 25070 and an anvil 25060 that is configuredto pivot relative to the lower jaw 25070. In some embodiments, the endeffector insert 25002 can comprise a staple cartridge 25000 that ispivotably connected to an anvil insert 25004. The end effector 12 can beconfigured to receive the end effector insert 25002 such that the staplecartridge 25000 fits within a staple cartridge channel 25072 of thelower jaw 25070, for example, and the anvil insert 25004 contacts theanvil 25060, for example. In various embodiments, the lower jaw 25070can comprise a plurality of securing members 25074 configured to securethe staple cartridge 25000 to the staple cartridge channel 25072. Insome embodiments, the anvil insert 25004 can comprise at least oneretaining protrusion configured to engage at least one retaining groovein the anvil 25060. The anvil insert 25004 can be configured tocorrespondingly pivot towards the staple cartridge 25000 when the anvil25060 pivots towards the lower jaw 25070, as described in greater detailherein.

Referring still to FIG. 172, the end effector insert 25002 can furthercomprise a retainer 25010. In various embodiments, the retainer 25010can securely engage at least one of the staple cartridge 25000 and theanvil insert 25004. In at least one embodiment, the retainer 25010 cancomprise at least one securing clip 25012 that can clip, engage, snap,clamp, and/or hook the staple cartridge 25000. As illustrated in FIG.172, the retainer 25010 can comprise two securing clips 25012 on eachlongitudinal side thereof, for example. In at least one such embodiment,the securing clips 25012 can be configured to clip onto a portion of thestaple cartridge 25000, for example. In various embodiments, a tissuethickness compensator can be held in position relative to the endeffector insert 25002 by the retainer 25010. For example, a tissuethickness compensator can be positioned between the retainer 25010 andthe staple cartridge 25000.

In various embodiments, when an operator is inserting the end effectorinsert 25002 into the end effector 12, the retainer 25010 can provide asolid or substantially solid element for the operator to grasp.Furthermore, the retainer 25010 can prevent premature deformation of atissue thickness compensator that is confined by the retainer 25010, forexample. In various embodiments, the retainer 25010 can be removed fromthe end effector 12 prior to utilizing the end effector 12 to cut and/orfasten tissue. In other embodiments, the retainer 25010 can remainpositioned in the end effector 12. For example, the retainer 25010 canbe transected by the cutting element 25052 (FIG. 207) as staples arefired from staples cavities 25002 (FIG. 207) in the staple cartridge25000. In various embodiments, the retainer 25010 can comprise apolymeric composition, such as a bioabsorbable, biocompatibleelastomeric polymer, for example. The retainer 25010 can furthercomprise a bioabsorbable polymer, such as, for example, lyophilizedpolysaccharide, glycoprotein, elastin, proteoglycan, gelatin, collagen,and/or oxidized regenerated cellulose (ORC), for example. In someembodiments, the retainer 25010 can comprise at least one therapeuticagent such as a pharmaceutically active agent or medicament.

Referring to FIG. 173, an end effector 26012 can comprise an anvil 26060and a lower jaw 26070. In various embodiments, a tissue compensator26020 can be releasably secured to the anvil 26060, the lower jaw 26070,and/or both the anvil 26060 and the lower jaw 26070. For example, afirst tissue compensator 26020 can be releasably secured to a staplecartridge 26000 in the lower jaw 26070 and a second tissue compensator26022 can be releasably secured to the anvil 26060. In variousembodiments, the first and second tissue compensators 26020, 26022 canbe deformable and/or resilient, similar to at least one tissue thicknesscompensator described herein. For example, the first and second tissuecompensators 26020, 26022 can comprise a polymeric composition, such asa bioabsorbable, biocompatible elastomeric polymer, for example. Thefirst and second tissue compensators 26020, 26022 can further comprise abioabsorbable polymer, such as, for example, lyophilized polysaccharide,glycoprotein, elastin, proteoglycan, gelatin, collagen, and/or oxidizedregenerated cellulose (ORC), for example. In some embodiments, the firstand second tissue compensators 26020, 26022 can comprise at least onetherapeutic agent such as a pharmaceutically active agent or medicament.

In some embodiments, the tissue compensator 26020, 26022 can comprise afirm or substantially firm tip 26024, 26026. For example, a first tip26024 can be positioned at the distal end of the first tissuecompensator 26020 and a second tip 26026 can be positioned at the distalend of the second tissue compensator 26022. In various embodiments, thetips 26024, 26026 may prevent or limit premature deformation of thetissue compensators 26020, 26022. For example, the tips 26024, 26026 canprotect the tissue compensators 26020, 26022 when the tissuecompensators 26020, 26022 are moved through a trocar and/or maneuveredaround a patient's tissue, for example. Similarly, referring to FIG.174, the end effector 12 can comprise a first tissue compensator 25020releasably secured to the staple cartridge 25000 in the lower jaw 25070and a second tissue compensator 25022 releasably secured to the anvil25060. In various embodiments, a tip 25026 can be positioned at thedistal end of the second tissue compensator 25022. The tip 25026 can bepositioned adjacent to a deformable and/or resilient portion of thetissue compensator 25022. In some embodiments, the tip 25026 can extendover and/or around a portion of the tissue compensator 25022, such thatthe tip 25026 protects the distal end and an intermediate portion of thetissue compensator 25022.

Referring to FIGS. 175-202, a sleeve 27010 can be configured to engagethe anvil 25060 of the end effector 12 of a surgical instrument, forexample. In various embodiments, the sleeve 27010 can comprise a prongedportion 27040 (FIGS. 176-179), a nose 27080 (FIGS. 186-189) and acompensator 27120 (FIGS. 180-182). In some embodiments, the sleeve 27010can be configured to release a compensator 27020 when a translatingfiring bar 25052 (FIG. 196) approaches the distal end of the endeffector 12. In various embodiments, the compensator 27020 can bedeformable and/or resilient, similar to at least one tissue thicknesscompensator described herein. For example, the compensator 27020 cancomprise a polymeric composition, such as a bioabsorbable, biocompatibleelastomeric polymer, for example. The compensator 27020 can furthercomprise a bioabsorbable polymer, such as, for example, lyophilizedpolysaccharide, glycoprotein, elastin, proteoglycan, gelatin, collagen,and/or oxidized regenerated cellulose (ORC), for example. In someembodiments, the compensator 27020 can comprise at least one therapeuticagent such as a pharmaceutically active agent or medicament. Referringprimarily to FIG. 175, the pronged portion 27040 can be positioned onand/or around an outer surface 25061 of the anvil 25060. In variousembodiments, the nose 27080 of the sleeve 27010 can be positioned atand/or around a distal portion of the anvil 25060. In some embodiments,the compensator 27020 can be positioned on and/or around an innersurface of the anvil 25060.

Referring still to FIG. 175, the pronged portion 27040 can comprise atleast one prong 27042 a. In various embodiments, as illustrated in FIGS.505-508, the pronged portion 27040 can comprise a first prong 27042 aand a second prong 27042 b. The prongs 27042 a, 27042 b can besymmetrical or substantially symmetrical, for example. In someembodiments, the first prong 27042 a can be asymmetrical relative to thesecond prong 27042 b. In various embodiments, the first and/or secondprongs 27042 a, 27042 b can narrow at the distal end thereof. Forexample, each prong 27042 a, 27042 b can comprise a narrowed end 27048.Referring primarily to FIG. 178, the pronged portion 27040 can becontoured, for example. In various embodiments, referring again to FIG.175, the contour of the pronged portion 27040 can match or substantiallymatch a contour of the outer surface 25061 of the anvil 25060, forexample. Referring primarily to FIGS. 178 and 179, the pronged portion27040 can also comprise at least one catch 27044 a extending from thefirst prong 27042 a. In some embodiments, a first catch 27044 a can bepositioned on a first side of the pronged portion 27040 and a secondcatch 27044 b can be positioned on a second side of the pronged portion27040. In various embodiments, the catches 27044 a, 27044 b can bepositioned at or near the proximal end of the pronged portion 27040, forexample. In some embodiments, the catches 27044 a, 27044 b can bepositioned at or near the distal end of the pronged portion 27040, suchas along the first and/or second prongs 27042 a, 27042 b, for example.In various embodiments, the catches 27044 a, 27044 b can extend along asubstantial length of the pronged portion 27040 and/or along a shorterlength of the pronged portion 27040. In some embodiments, a plurality ofcatches 27044 a, 27044 b can be positioned along each longitudinal sideof the pronged portion, for example. Referring primarily to FIG. 179,the first catch 27044 a can comprise a first catch extension 27046 aand/or the second catch 27044 b can comprise a second catch extension27046 b. In various embodiments, the first catch extension 27046 a canprotrude from at least a portion of the catch 27044 a and the secondcatch extension 27046 b can protrude from at least a portion of thecatch 27044 b, for example. Further, the first catch extension 27046 aand the second catch extension 27046 b can each be configured to engagea gap 27128 (FIG. 181) in the compensator 27020, as described in greaterdetail herein.

Referring now to FIG. 201, the compensator 27020 for the sleeve 27010can comprise a longitudinal protrusion 27024 and an edge 27026 on eachlongitudinal side of the compensator 27020. In various embodiments, thecompensator 27020 can be positioned adjacent to an inner surface 25063of the anvil 25060. Further, when the sleeve 27010 is positioned on theanvil 25060, the longitudinal protrusion 27024 can be substantiallyaligned with and/or positioned within a longitudinal slot 25062 in theanvil 25060. The edges 27026 of the compensator 27020 can at leastpartially wrap around the anvil 25060 towards the outer surface 25061thereof. Referring primarily to FIGS. 180-181, a compensator 27120 for asleeve 27110 can comprise a body 27122 having a longitudinal protrusion27124 that extends along at least a portion of the body 27122. Thelongitudinal protrusion 27124 can define a longitudinal path along themidline of the body 27122, for example. In various embodiments, thelongitudinal protrusion 27124 can be received by the longitudinal slot25062 (FIG. 201) in the anvil 25060 when the sleeve 27110 is positionedon the anvil 25060. Referring primarily to FIG. 182, the longitudinalprotrusion 27124 can comprise a rounded projection. For example, thecross-section of the longitudinal protrusion 27124 can form an arcand/or partial ring. In other embodiments, the longitudinal protrusion27124 can comprise an angular and/or stepped projection. The compensator27120 can further comprise an edge 27126, which can be straight, bent,fluted, wavy, and/or zigzagged, for example. In various embodiments, theedge 27126 can comprise gaps 27128 that can be configured to receive thecatch extensions 27046 a, 27046 b (FIG. 179) when the assembled sleeve27110 is positioned on the anvil 25060. The catch extensions 27046 a,27046 b can fit through the gap 27128 to engage the anvil 25060 suchthat the catch extensions 27046 a, 27046 b help to secure the sleeve27110 to the anvil 25060, for example.

Referring primarily to FIGS. 183-185, a compensator 27220 for a sleeve27210 can comprise a body 27222 comprising a longitudinal protrusion27224 extending along at least a portion of the body 27222. In variousembodiments, similar to the above, the longitudinal protrusion 27224 canbe received by the longitudinal slot 25062 (FIG. 202) in the anvil 25060when the sleeve 27210 is positioned on the anvil 25060. Referringprimarily to FIG. 185, the longitudinal protrusion 27224 can comprise anangular projection such that the cross-section of the protrusion 70224forms a substantially rectangular shape. The compensator 27220 canfurther comprise an edge 27226, which can be straight, bent, fluted,wavy, and/or zigzagged, for example. In various embodiments, the edge27226 can comprise gaps 27228 that can be configured to receive thecatch extensions 27046 a, 27046 b (FIG. 179) when the assembled sleeve27210 is positioned on the anvil 25060. The catch extensions 27046 a,27046 b can fit through the gaps 27228 and engage the anvil 25060 suchthat the catch extensions 27046 a, 27046 b help to secure the sleeve27210 to the anvil 25060, for example. In various embodiments, thecompensator 27220 can further comprise a plurality of ribs 27229 thatlaterally traverse the body 27222 of the compensator 27220. The ribs27229 can support the body 27222 of the compensator 27220 when thesleeve 27210 is positioned on the anvil 25060 and/or when thecompensator 27220 contacts tissue.

Referring to FIGS. 386-390, the nose 27080 of the sleeve 27010 cancomprise an alignment ridge 27082 that can be substantially aligned withthe longitudinal slot 25062 (FIG. 201) in the anvil 25060. When thealignment ridge 27082 is aligned with the longitudinal slot 25062 andwhen the sleeve 27010 is positioned on the anvil 25060, the nose 27082can at least partially surround a distal portion of the pronged portion27040 of the sleeve 27010. For example, the narrowed end 27048 of eachprong 27042 a, 27042 b can be positioned within the nose 27080 when thesleeve 27010 is positioned on the anvil 25060. As described in greaterdetail herein, the nose 27080 can flex the prongs 27042 a, 27042 bcloser together and/or downward when the pronged portion 27042 isengaged with the nose 27080. Furthermore, as illustrated in FIG. 190,when the narrowed ends 27048 of the pronged portion 27040 are positionedwithin the nose 27080, the catches 27044 a, 27044 b on the prongedportion 27040 can engage the edges 27026 of the compensator 27020, forexample. As a result of such engagement, the compensator 27010 can besecured to the anvil 25060.

Referring to FIGS. 191-195, when the nose 27080 is engaged with thepronged portion 27040 of the sleeve 27010, the compensator 27020 can besecured to the anvil 25060. The nose 27080 can remain engaged with thepronged portion 27040 as the firing bar 25050 translates along a portionof the longitudinal slot 25062 in the anvil 25060. Referring now toFIGS. 195-200, when the cutting element 25052 on the firing bar 25050,and/or any other suitable portion of the firing bar 25050, such asretaining flange 25054, for example, approaches the distal end of theanvil 25060, the firing bar 25050 can disengage the nose 27080 from thepronged portion 27040. The firing bar 25050 can, for example, contactthe nose 27080 and push the nose 27080 off of the anvil 25060 such thatthe nose 27080 becomes disconnected from the pronged portion 27040 ofthe sleeve 27010. Referring now to FIG. 202, when the nose 27080 isdisengaged with the pronged portion 27040, the first and second prongs27042 a, 27042 b can be configured to flex away from the anvil 25060.For example, when the pronged portion 27070 is engaged with the nose27080, the prongs 27042 a, 27042 b can be flexed closer together and/ordownwards towards the anvil 25060 and held in such a position by thenose 27080. In various embodiments, the prongs 27042 a, 27042 b can beheld under a spring load by the nose 27080 such that the prongs 27042 a,27042 b seek to rebound to a neutral configuration once the nose 27080is disengaged from the prongs 27042 a, 27042 b. In other embodiments,the prongs 27042 a, 27042 b can be sufficiently deformable such that theprongs 27042 a, 27042 b can be deformed or splayed outwardly by thefiring bar 25050 once the nose 27080 is disengaged therefrom. When theprongs 27042 a, 27042 b move away from the anvil 25060, the catches27044 a, 27044 b along a longitudinal side of each prong 27042 a, 27042b can disengage the compensator 27020, which can allow the compensator27020 to be released from the anvil 25060.

Referring to FIGS. 203-209, the end effector 12 of a surgicalinstrument, for example, can be configured to receive an end effectorinsert 28010. In various embodiments, the end effector insert 28010 cancomprise a compensator body 28012 and at least one clip 28014 a, 28014b. In various embodiments, the end effector insert 28010 can comprise aproximal clip 28014 b at the proximal end of the compensator body 28012and a distal clip 28014 a at the distal end of the compensator body28012, for example. Referring primarily to FIG. 206, the distal clip28014 a can be secured to the anvil 25060 of the end effector 12 at ornear the distal end of the anvil 25060. For example, the distal clip28014 a can be substantially aligned with and/or partially positionedwithin the longitudinal slot 25062 of the anvil 25060. Referringprimarily to FIG. 207, the proximal clip 28014 b can be secured to astaple cartridge 25000 in the lower jaw 25070 of the end effector 12(FIG. 208). The proximal clip 28014 b can be secured to the staplecartridge 25000 at or near the proximal end of the staple cartridge25000. For example, the proximal clip 28014 b can be substantiallyaligned with and/or positioned within a longitudinal slot 25004 in thestaple cartridge 25000.

Referring now to FIGS. 208 and 209, the end effector insert 28010 can beinserted into the end effector 12 of a surgical instrument. In variousembodiments, at least a portion of the end effector insert 28010, suchas the compensator body 28012, distal clips 28014 a, and/or proximalclip 28014 b, can be deformable and/or resilient, for example. When theend effector insert 28010 is inserted into the end effector 12, thedistal and/or the proximal clips 28014 a, 28014 b can bend or flex. Whenthe clips 28014 a, 28014 b are flexed, for example, the clips 28014 a,28014 b can seek to return to their initial, undeformed configurationand can generate a corresponding springback or restoring force, forexample. In various embodiments, when the end effector insert 28010 ispositioned within the end effector 12, the end effector insert 28010 canapply a spring load to the end effector 12. In some embodiments, the endeffector insert 28010 can be solid or substantially solid such that anoperator can grasp the insert 28010 when the operator is inserting theend effector insert 28010 and staple cartridge 25000 into the endeffector 12.

In some embodiments, the end effector insert 28010 can be removed fromthe end effector 12 prior to cutting and/or fastening operations of theend effector 12. In other embodiments, the end effector insert 28010 canremain positioned in the end effector 12 during cutting and/or firingoperations. For example, the end effector insert 28010 can be transectedby the cutting element 25052 as staples are fired from their staplescavities 25002 (FIG. 207) in the staple cartridge 25000. In variousembodiments, the end effector insert 28010 can comprise a tissuethickness compensation material, similar to at least one of the tissuethickness compensators described herein. For example, the end effectorinsert 28010 can comprise a polymeric composition, such as abioabsorbable, biocompatible elastomeric polymer, for example. The endeffector insert 28010 can further comprise a bioabsorbable polymer, suchas, for example, lyophilized polysaccharide, glycoprotein, elastin,proteoglycan, gelatin, collagen, and/or oxidized regenerated cellulose(ORC), for example. In some embodiments, the end effector insert 28010can comprise at least one therapeutic agent such as a pharmaceuticallyactive agent or medicament.

Referring to FIGS. 210-215, a tissue thickness compensator 29020 can bepositioned in the end effector 12 of a surgical instrument. The tissuethickness compensator 29020 can be substantially similar to at least oneof the tissue thickness compensators described herein. For example, thetissue thickness compensator 29020 can be sufficiently deformable andresilient such that deformation of the tissue thickness compensator29020 generates a springback or restoring force. In various embodiments,referring primarily to FIG. 211, a static charge can attract the tissuethickness compensator 29020 to the anvil 25060 of the end effector 12such that the static charge secures the tissue thickness compensator29020 to the anvil 25060. In various embodiments, the static charge canbe neutralized such that the anvil 25060 releases the tissue thicknesscompensator 29020. Additionally or alternatively, referring now to FIG.212, the tissue thickness compensator 29020 can be secured to the anvil25060 by at least one suction element 29022. For example, a plurality ofmicro-suction elements 29022 on a surface of the tissue thicknesscompensator 29020 can releasably secure the tissue thickness compensator29020 to the anvil 25060. Additionally or alternatively, referring toFIG. 213, hook and loop fasteners 29024 can secure the tissue thicknesscompensator 29020 to the anvil 25060. For example, a surface of thetissue thickness compensator 29020 can comprise a plurality of hookfasteners 29024 a and a surface of the anvil 25060 can comprise aplurality of loop fasteners 29024 b, for example. The hook fasteners29024 a can engage the loop fasteners 29024 b such that the tissuethickness compensator 29020 is releasably secured to the anvil 25060.

Additionally or alternatively, referring now to FIG. 214, the tissuethickness compensator 29020 can be secured to the anvil 25060 by a band29026. In some embodiments, the band 29026 can comprise an elastomericpolymer and/or can be tied or knotted around the anvil 25060. When theband 29026 is removed from the anvil 25060, the tissue thicknesscompensator 29020 can be released from the anvil 25060. To facilitateremoval of the band 29026, it can be stretched and/or cut, for example.In various embodiments, a plurality of bands 29026 can secure the tissuethickness compensator 29020 to the anvil 25060. Alternatively oradditionally, referring now to FIG. 215, the tissue thicknesscompensator 29020 can be secured to the anvil 25060 by a sock 29028positioned at the distal end of the tissue thickness compensator 29020.The sock 29028 can be configured to receive the distal end of the anvil25060 therein, for example. In some embodiments, an alignment ledge29029 on the tissue thickness compensator 29020 can be aligned withand/or positioned within the longitudinal slot 25062 in the anvil 25060.For example, the alignment ledge 29029 can slide within the longitudinalslot 25062 as the tissue thickness compensator 29020 is positioned onand/or removed from the anvil 25060.

Referring to FIGS. 216-218, a tissue thickness compensator 30020 can bepositioned on the anvil 25060 of the end effector 12 of the surgicalinstrument. In various embodiments, the tissue thickness compensator30020 can comprise a body 30022 and a pocket 30024. In at least oneembodiment, a compensator material 30026 can be retained between thebody 30022 and the pocket 30024, for example. In some embodiments, thecompensator material 30026 can comprise a bioabsorbable polymer, suchas, for example, lyophilized polysaccharide, glycoprotein, elastin,proteoglycan, gelatin, collagen, and/or oxidized regenerated cellulose(ORC), for example. Additionally or alternatively, the compensatormaterial 30026 can comprise at least one therapeutic agent such as apharmaceutically active agent or medicament. In various embodiments, thetissue thickness compensator 30020 can be deformable and/or resilient,similar to at least one tissue thickness compensator described herein.For example, the tissue thickness compensator 30020 can comprise apolymeric composition, such as a bioabsorbable, biocompatibleelastomeric polymer, for example. The tissue thickness compensator 30020can further comprise a bioabsorbable polymer, such as, for example,lyophilized polysaccharide, glycoprotein, elastin, proteoglycan,gelatin, collagen, and/or oxidized regenerated cellulose (ORC), forexample.

Referring primarily to FIG. 217, the body 30022 of the tissue thicknesscompensator 30020 can comprise an alignment element 30028 that can bereceived within the longitudinal slot 25062 of the anvil 25060 when thetissue thickness compensator 30020 is secured to the anvil 25060. Insome embodiments, the body 30022 can comprise a stepped thickness suchthat the geometry of the body 30022 substantially corresponds with thegeometry of the anvil 25060. Further, in various embodiments, the body30022 can comprise longitudinal flanges 30029. In at least one suchembodiment, a longitudinal flange 30029 can extend along eachlongitudinal side of the body 30022 of the tissue thickness compensator30020, for example. In various embodiments, the longitudinal flanges30029 can at least partially wrap around the anvil 25060 to secure thetissue thickness compensator 30020 to the anvil 25060. Further, thelongitudinal flanges 30029 can be sufficiently resilient such that thelongitudinal flanges 30029 can flex to accommodate and/or engage theanvil 25060, for example. In various embodiments, the longitudinalflanges 30029 can exert a clamping force on the anvil 25060 when theflanges 30029 engage the anvil 25060. In some embodiments, the pocket30024 can comprise an indentation 30025. When the tissue thicknesscompensator 30020 is secured to the anvil 25060, the indentation 30025can be substantially aligned with the longitudinal slot 25062 in theanvil 25060, for example. In various embodiments, the tissue thicknesscompensator 30020 can be thinner at the indentation 30025 such that thetranslating cutting element 25052 (FIG. 207) severs the tissue thicknesscompensator 30020 where it is thinner.

Referring now to FIGS. 219 and 220, a tissue thickness compensator 30120can comprise a body 30122 that is configured to retain compensationmaterial 30026 therein. In various embodiments, the tissue thicknesscompensator 30120 can comprise an alignment element 30128, anindentation 30125, and/or longitudinal flanges 30129, similar to atleast one of the embodiments described herein. In some embodiments, thetissue thickness compensator 30120 can also comprise a latch 30124 thatcan be moved between an open position and a closed position. When thelatch 30124 is in the closed position, as illustrated in FIG. 219, thecompensation material 30026 can be enclosed within the body 30122 of thetissue thickness compensator 30120 and, when the latch 30124 is in theopen position, as illustrated in FIG. 220, the compensation material30026 can escape from the body 30122. Similar to at least one of thetissue thickness compensators described herein, the tissue thicknesscompensator 30120 can be deformable and/or resilient. For example, thetissue thickness compensator 30120 can comprise a polymeric composition,such as a bioabsorbable, biocompatible elastomeric polymer, for example.The tissue thickness compensator 30120 can further comprise abioabsorbable polymer, such as, for example, lyophilized polysaccharide,glycoprotein, elastin, proteoglycan, gelatin, collagen, and/or oxidizedregenerated cellulose (ORC), for example. Owing to the resiliency of thetissue thickness compensator 30120, at least a portion of the body 30122can be flexed to move the latch 30124 between the open position and theclosed position. In at least one embodiment, the body 30122 of thetissue thickness compensator 30120 can remain attached to the anvil whenthe anvil is removed from the surgical site. In at least one suchembodiment, the body 30122 can be configured to tear away from anystaples that may have captured the body 30122 therein.

Referring to FIG. 221, a tissue thickness compensator 30220 can comprisea body 30222 and a pocket 30224. The compensator material 30026 can beretained between the body 30222 and the pocket 30224, for example. Invarious embodiments, the tissue thickness compensator 30220 can comprisean alignment element, an indentation, and/or longitudinal flanges 30229,similar to at least one of the embodiments described herein. Further, atleast one longitudinal flange 30229 can comprise a groove, or slot,30228, which can be configured to receive a tab 30225 extending from thepocket 30224 of the tissue thickness compensator 30220. In such anembodiment, engagement of the groove 30228 and the tab 30225 can connectthe body 30222 and the pocket 30224. Further, in such an embodiment, thegroove 30028 and tab 30025 connection can enclose and/or retain thecompensation material 30026 within the tissue thickness compensator30220. Referring now to FIG. 222, in various embodiments, a pocket 30324of a tissue thickness compensator 30320 can comprise an anchor 30325extending therefrom. Further, the tissue thickness compensator 30320 cancomprise a body 30322 having an opening 30328. In various embodiments,the anchor 30325 can extend from the pocket 30324 to engage the opening30328 in the body 30322. In such an arrangement, the pocket 30324 andthe body 30222 can encase the compensation material 30026 therebetween.In at least one embodiment, the tissue thickness compensator 30320 canfurther comprise one or more flanges 30229 which can be mounted to theanvil in order to retain the body 30322 to the anvil.

Referring now to FIG. 223, a tissue thickness compensator 30420 cancomprise a body 30422 and a pocket 30424. In various embodiments, thecompensation material 30026 can be retained between the body 30422 andthe pocket 30424 of the tissue thickness compensator 30420. In someembodiments, the body 30422 can comprise an orifice 30428 and the pocket30424 can comprise an anchor 30425. The anchor 30425 can extend from thepocket 30424 and through the orifice 30428 of the body 30422, forexample. In various embodiments, the anchor 30425 can engage the anvil25060 when the tissue thickness compensator 30420 is secured to theanvil 25060, for example. The anchor 30525 can be sufficientlydeformable and resilient such that the anchor 30425 flexes when itengages the anvil 25060. Further, in some embodiments, the flexed anchor30425 can apply a clamping force to the anvil 25060 to secure or assistin securing the tissue thickness compensator 30420 to the anvil 25060.In other embodiments, an anchor may not extend completely through anorifice in the compensator body. Referring to FIG. 224, an anchor 30525on a pocket 30524 of a tissue thickness compensator 30520 can engage anorifice 30528 in a body 30522 of the tissue thickness compensator 30520.In various embodiments, the anchor 30525 can engage the orifice 30528 tosecure the pocket 30524 to the body 30522. For example, the orifice30528 can comprise a necked portion that extends to a socket. The anchor30525 can comprise securing edge, which can pass through the neckedportion and engage the socket to secure the anchor 20525 within theorifice 30528. Similar to at least one of the embodiments describedherein, the tissue thickness compensator 30520 can also comprise analignment element, an indentation, and/or longitudinal flanges 30529,for example.

Referring to FIGS. 225-227, a tissue thickness compensator 31020 can beconfigured to engage an anvil 31060 of an end effector 31012 of asurgical instrument. In various embodiments, the tissue thicknesscompensator 31020 can comprise an outer film 31022, an inner film 31024and a compensation material 31026 positioned therebetween. In variousembodiments, the tissue thickness compensator 31020 can be deformableand/or resilient, similar to at least one of the tissue thicknesscompensators described herein. For example, the compensation material31026 can comprise a polymeric composition, such as a bioabsorbable,biocompatible elastomeric polymer, for example. The tissue thicknesscompensator 31020 can further comprise a bioabsorbable polymer such as,for example, lyophilized polysaccharide, glycoprotein, elastin,proteoglycan, gelatin, collagen, and/or oxidized regenerated cellulose(ORC), for example. In some embodiments, the tissue thicknesscompensator 31020 can comprise at least one therapeutic agent such as apharmaceutically active agent or medicament. In various embodiments, thecompensation material 31206 of the tissue thickness compensator 31020can comprise a therapeutic agent.

The inner film 31024 can be positioned adjacent to staple formingpockets 31066 in the anvil 31060, for example. Referring primarily toFIG. 225, the inner film 31024 can comprise a stepped geometry such thatthe geometry of the inner film 31024 substantially corresponds to thegeometry of the anvil 31060. The inner film 31024 can further comprisean alignment ridge 31028, which can be substantially aligned with and/orparallel to a longitudinal slot 31062 in the anvil 31060, for example.As described in greater detail herein, the inner film 31024 can comprisean inner flange 31025 extending from each longitudinal side of the innerfilm 31024 and terminating in a catch 31027. The outer film 31022 cancomprise a body 31021 and at least one outer flange 31023, for example.In various embodiments, an outer flange 31023 can extend from eachlongitudinal side of the body 31021, for example. In variousembodiments, the outer flange 31023 can be secured to the inner flange31025 such that the compensation material 31026 is retained between theouter film 31022 and the inner film 31024.

Referring primarily to FIG. 227, the anvil 31060 can comprise an outersurface 31061 and at least one groove 31064 along at least a portion ofthe outer surface 31061. In various embodiments, a catch 31027 on theinner flange 31025 of the inner film 31024 can be positioned within agroove 31064. Referring to FIG. 226, for example, the tissue thicknesscompensator 31020 can be slid around the anvil 31060. In variousembodiments, the grooves 31064 on the anvil 31060 can extend to thedistal end of the anvil 31060. In such embodiments, the catches 31027 ofthe tissue thickness compensator 31020 can slide into the grooves 31064and along a length of the tissue thickness compensator 31020.

In various embodiments, referring now to FIGS. 228 and 229, a tissuethickness compensator 31120 can comprise a compensation material 31026and at least one connector 31124. Each connector 31124 can extend aroundthe compensation material 31026 and can terminate in a catch 31127 onopposite ends thereof. In various embodiments, the catches 31127 can bepositioned within the grooves 31064 of the anvil 31060 to fasten thetissue thickness compensator 31120 to the anvil 31060. In variousembodiments, the grooves 31164 on the anvil 31060 can extend to thedistal end of the anvil 31060. In such embodiments, the catches 31127 ofthe connectors 31124 can slide into the grooves 31064. In otherembodiments, the connectors 31224 can be resilient such that they canflex and snap around the anvil 31060. In use, the connectors 31224 canhold the compensation material 31026 in place until the compensationmaterial 31026 detaches from the anvil 31060. In certain circumstances,the connectors 31224 can remain attached to the anvil 31060 and can beremoved from the surgical site with the anvil. In certain othercircumstances, the connectors 31224 can detach from the anvil 31060 andcan be implanted with the compensation material 31026.

Referring to FIGS. 230-236, a tissue thickness compensator 32020 cancomprise a body portion 32022, at least one longitudinal flange 32024,and at least one pocket 32026. In various embodiments, the tissuethickness compensator 31020 can be deformable and/or resilient, similarto at least one of the tissue thickness compensators described herein.For example, the compensation material 31026 can comprise a polymericcomposition such as a bioabsorbable, biocompatible elastomeric polymer,for example. The tissue thickness compensator 31020 can further comprisea bioabsorbable polymer such as, for example, lyophilizedpolysaccharide, glycoprotein, elastin, proteoglycan, gelatin, collagen,and/or oxidized regenerated cellulose (ORC), for example. In variousembodiments, the longitudinal flange 32024 can extend along eachlongitudinal side of the body portion 32022. Referring primarily to FIG.233, the longitudinal flanges 32024 of the tissue thickness compensator32020 can be configured to engage the anvil 25060. For example, thetissue thickness compensator 32020 can slide onto the anvil 25060 andthe longitudinal flanges 32024 and can at least partially wrap around aportion of the anvil 25060. In such embodiments, the flanges 32024 cansecure the tissue thickness compensator 32020 to the anvil 25060, forexample. In various embodiments, when the tissue thickness compensator32020 is secured to the anvil, the body portion 32022 of the tissuethickness compensator 32020 can overlap staple forming pockets 25066 onthe inner surface of the anvil 25060.

Further to the above, in various embodiments, a plurality of pockets32026 can laterally traverse the body portion 32022. Referring primarilyto FIG. 234, the plurality of pockets 32026 can comprise at least onetherapeutic agent such as a pharmaceutically active agent or medicament.In various embodiments, a plurality of first pockets 32026 a cancomprise a first therapeutic agent or combination thereof and aplurality of second pockets 32026 b can comprise a second therapeuticagent or combination thereof. The first pockets 32026 a and the secondpockets 32026 b can be alternatingly positioned along the body portion32022, for example. Further, in various embodiments, when the firsttherapeutic agent is released from the first pocket 32026 a and thesecond therapeutic agent is released from the second pocket 32026 b, thefirst and second therapeutic agents can be configured to react with eachother. Referring to FIG. 236, the pockets 32026 can release thetherapeutic agent(s) retained therein when the cutting element 25052 onthe firing bar 25050 translates along the longitudinal slot 25062 in theanvil 25060, for example.

In various embodiments, referring now to FIG. 237, an end effector of asurgical stapling instrument can comprise an anvil 32560 and a staplecartridge 32500 comprising a tissue thickness compensator 32520. Similarto the above, the staple cartridge 32500 can comprise a plurality ofstaples 32530 at least partially contained therein which can be ejectedtherefrom to capture the tissue thickness compensator 32520 therein.Also similar to the above, the staples 32530 can penetrate the tissuethickness compensator 32520 and contact staple forming pockets 32562defined in the anvil 32560. In certain embodiments, referring now toFIG. 239, the anvil 32560 can further comprise a layer 32570 attachedthereto which can be configured to retain a tissue thickness compensator32580 to the anvil 32560. In at least one such embodiment, the layer32570 can comprise a chargeable layer which can be configured to holdand/or generate an electrostatic charge and attract the tissue thicknesscompensator 32580 thereto. More specifically, in various embodiments,Van der Waals molecular forces, whether actively or passively actuated,for example, can hold the tissue thickness compensator 32580 to thelayer 32570. In certain embodiments, the chargeable layer 32570 can bein electrical communication with a handle of the surgical staplinginstrument which can comprise a control configured to selectively couplethe chargeable layer 32570 with a power source and, as a result, allowan electrostatic charge to be selectively generated within thechargeable layer 32570. In at least one such embodiment, the chargeablelayer 32570 can comprise conductive electrodes embedded within apolymer, for example. In any event, the statically-charged layer 32570can attract oppositely-charged particles in the tissue thicknesscompensator 32580 and hold the tissue thickness compensator 32580 to theanvil. In certain embodiments, referring now to FIG. 238, the chargeablelayer 32570 can comprise a grid, or lattice, of conductors 32571 whichare in electrical communication with one another. In at least one suchembodiment, the conductors can be positioned and arranged such that theysurround the staple forming pockets 32562 defined in the anvil 32560. Insuch embodiments, staples 32530 can be ejected from the staple cartridge32500 and then deformed by the anvil 32560 without capturing theconductors 32571 therein. In various circumstances, the chargeable layer32570 can be uncoupled from the power source after the staples 32530have been engaged with the tissue thickness compensator 32580 such thatthe electrostatic charge in the layer 32570 can dissipate. In certainother circumstances, the chargeable layer 32570 can be uncoupled fromthe power source prior to the staples 32530 being fired. In any event,as the electrostatic charge dissipates, the anvil 32560 can be re-openedand the layer 32570 can be moved away from the tissue thicknesscompensator 32580. In some embodiments, the electrostatic charge mayneed to dissipate completely before the layer 32570 can be detached fromthe tissue thickness compensator 32580 while, in other embodiments, thelayer 32570 can be detached from the tissue thickness compensator 32580before the electrostatic charge in the layer 32570 has completelydissipated. In certain embodiments, as a result of the above, the tissuethickness compensator 32580 can be attached to the anvil 32560 withoutthe use of a chemical adhesive.

In various embodiments, further to the above, the layer 32570 can alsoprovide feedback capability to the handle of the surgical staplinginstrument. In at least one such embodiment, the layer 32570 can bepressure sensitive and can be configured to detect the clamping pressurebeing applied thereto by the anvil 32560, for example.

In various embodiments, further to the above, a tissue thicknesscompensator can be comprised of a biocompatible material. Thebiocompatible material, such as, a foam, may comprise tackifiers,surfactants, fillers, cross-linkers, pigments, dyes, antioxidants andother stabilizers and/or combinations thereof to provide desiredproperties to the material. In certain embodiments, a biocompatible foammay comprise a surfactant. The surfactant may be applied to the surfaceof the material and/or dispersed within the material. Without wishing tobe bound to any particular theory, the surfactant applied to thebiocompatible material may reduce the surface tension of the fluidscontacting the material. For example, the surfactant may reduce thesurface tension of water contacting the material to accelerate thepenetration of water into the material. In various embodiments, thewater may act as a catalyst. The surfactant may increase thehydrophilicity of the material.

In various embodiments, the surfactant may comprise an anionicsurfactant, a cationic surfactant, and/or a non-ionic surfactant.Examples surfactants include, but are not limited to polyacrylic acid,methalose, methyl cellulose, ethyl cellulose, propyl cellulose, hydroxyethyl cellulose, carboxy methyl cellulose, polyoxyethylene cetyl ether,polyoxyethylene lauryl ether, polyoxyethylene octyl ether,polyoxyethylene octylphenyl ether, polyoxyethylene oleyl ether,polyoxyethylene sorbitan monolaurate, polyoxyethylene stearyl ether,polyoxyethylene nonylphenyl ether, dialkylphenoxy poly(ethyleneoxy)ethanol, and polyoxamers, and combinations thereof. In at least oneembodiment, the surfactant may comprise a copolymer of polyethyleneglycol and polypropylene glycol. In at least one embodiment, thesurfactant may comprise a phospholipid surfactant. The phospholipidsurfactant may provide antibacterial stabilizing properties and/ordisperse other materials in the biocompatible material. In variousembodiments, the tissue thickness compensator may comprise at least onemedicament. The tissue thickness compensator may comprise one or more ofthe natural materials, non-synthetic materials, and/or syntheticmaterials described herein. In certain embodiments, the tissue thicknesscompensator may comprise a biocompatible foam comprising gelatin,collagen, hyaluronic acid, oxidized regenerated cellulose, polyglycolicacid, polycaprolactone, polylactic acid, polydioxanone,polyhydroxyalkanoate, poliglecaprone, and combinations thereof. Incertain embodiments, the tissue thickness compensator may comprise afilm comprising the at least one medicament. In certain embodiments, thetissue thickness compensator may comprise a biodegradable filmcomprising the at least one medicament. In certain embodiments, themedicament may comprise a liquid, gel, and/or powder. In variousembodiments, the medicaments may comprise anticancer agents, such as,for example, cisplatin, mitomycin, and/or adriamycin.

In various embodiments, the tissue thickness compensator may comprise abiodegradable material to provide controlled elution or release of theat least one medicament as the biodegradable material degrades. Invarious embodiments, the biodegradable material may degrade maydecompose, or loses structural integrity, when the biodegradablematerial contacts an activator, such as, for example an activator fluid.In various embodiments, the activator fluid may comprise saline or anyother electrolyte solution, for example. The biodegradable material maycontact the activator fluid by conventional techniques, including, butnot limited to spraying, dipping, and/or brushing. In use, for example,a surgeon may dip an end effector and/or a staple cartridge comprisingthe tissue thickness compensator comprising the at least one medicamentinto an activator fluid comprising a salt solution, such as sodiumchloride, calcium chloride, and/or potassium chloride. The tissuethickness compensator may release the medicament as the tissue thicknesscompensator degrades. In certain embodiments, the elution or release ofthe medicament from the tissue thickness compensator may becharacterized by a rapid initial elution or release rate and a slowersustained elution or release rate.

In various embodiments, a tissue thickness compensator, for example, canbe comprised of a biocompatible material which may comprise an oxidizingagent. In various embodiments, the oxidizing agent may be an organicperoxide and/or an inorganic peroxide. Examples of oxidizing agents mayinclude, but are not limited to, hydrogen peroxide, urea peroxide,calcium peroxide, and magnesium peroxide, and sodium percarbonate. Invarious embodiments, the oxidizing agent may comprise peroxygen-basedoxidizing agents and hypohalite-based oxidizing agents, such as, forexample, hydrogen peroxide, hypochlorous acid, hypochlorites,hypocodites, and percarbonates. In various embodiments, the oxidizingagent may comprise alkali metal chlorites, hypochlorites and perborates,such as, for example, sodium chlorite, sodium hypochlorite and sodiumperborate. In certain embodiments, the oxidizing agent may comprisevanadate. In certain embodiments, the oxidizing agent may compriseascorbic acid. In certain embodiments, the oxidizing agent may comprisean active oxygen generator. In various embodiments, a tissue scaffoldmay comprise the biocompatible material comprising an oxidizing agent.

In various embodiments, the biocompatible material may comprise aliquid, gel, and/or powder. In certain embodiments, the oxidizing agentmay comprise microparticles and/or nanoparticles, for example. Forexample, the oxidizing agent may be milled into microparticles and/ornanoparticles. In certain embodiments, the oxidizing agent may beincorporated into the biocompatible material by suspending the oxidizingagent in a polymer solution. In certain embodiments, the oxidizing agentmay be incorporated into the biocompatible material during thelyophylization process. After lyophylization, the oxidizing agent may beattached to the cell walls of the biocompatible material to interactwith the tissue upon contact. In various embodiments, the oxidizingagent may not be chemically bonded to the biocompatible material. In atleast one embodiment, a percarbonate dry power may be embedded within abiocompatible foam to provide a prolonged biological effect by the slowrelease of oxygen. In at least one embodiment, a percarbonate dry powermay be embedded within a polymeric fiber in a non-woven structure toprovide a prolonged biological effect by the slow release of oxygen. Invarious embodiments, the biocompatible material may comprise anoxidizing agent and a medicament, such as, for example, doxycycline andascorbic acid.

In various embodiments, the biocompatible material may comprise a rapidrelease oxidizing agent and/or a slower sustained release oxidizingagent. In certain embodiments, the elution or release of the oxidizingagent from the biocompatible material may be characterized by a rapidinitial elution or release rate and a slower sustained elution orrelease rate. In various embodiments, the oxidizing agent may generateoxygen when the oxidizing agent contacts bodily fluid, such as, forexample, water. Examples of bodily fluids may include, but are notlimited to, blood, plasma, peritoneal fluid, cerebral spinal fluid,urine, lymph fluid, synovial fluid, vitreous fluid, saliva,gastrointestinal luminal contents, and/or bile. Without wishing to bebound to any particular theory, the oxidizing agent may reduce celldeath, enhance tissue viability and/or maintain the mechanical strengthof the tissue to tissue that may be damaged during cutting and/orstapling.

In various embodiments, the biocompatible material may comprise at leastone microparticle and/or nanoparticle. The biocompatible material maycomprise one or more of the natural materials, non-synthetic materials,and synthetic materials described herein. In various embodiments, thebiocompatible material may comprise particles having a mean diameter ofabout 10 nm to about 100 nm and/or about 10 □m to about 100 □m, such as,for example, 45-50 nm and/or 45-50 □m. In various embodiments, thebiocompatible material may comprise biocompatible foam comprising atleast one microparticle and/or nanoparticle embedded therein. Themicroparticle and/or nanoparticle may not be chemically bonded to thebiocompatible material. The microparticle and/or nanoparticle mayprovide controlled release of the medicament. In certain embodiments,the microparticle and/or nanoparticle may comprise at least onemedicament. In certain embodiments, the microparticle and/ornanoparticle may comprise a hemostatic agent, an anti-microbial agent,and/or an oxidizing agent, for example. In certain embodiments, thetissue thickness compensator may comprise a biocompatible foamcomprising an hemostatic agent comprising oxidized regeneratedcellulose, an anti-microbial agent comprising doxycline and/orGentamicin, and/or an oxidizing agent comprising a percarbant. Invarious embodiments, the microparticle and/or nanoparticle may providecontrolled release of the medicament up to three days, for example.

In various embodiments, the microparticle and/or nanoparticle may beembedded in the biocompatible material during a manufacturing process.For example, a biocompatible polymer, such as, for example, a PGA/PCL,may contact a solvent, such as, for example, dioxane to form a mixture.The biocompatible polymer may be ground to form particles. Dryparticles, with or without ORC particles, may be contacted with themixture to form a suspension. The suspension may be lyophilized to forma biocompatible foam comprising PGA/PCL having dry particles and/or ORCparticles embedded therein.

In various embodiments, the tissue thickness compensators or layersdisclosed herein can be comprised of an absorbable polymer, for example.In certain embodiments, a tissue thickness compensator can be comprisedof foam, film, fibrous woven, fibrous non-woven PGA, PGA/PCL(Poly(glycolic acid-co-caprolactone)), PLA/PCL (Poly(lacticacid-co-polycaprolactone)), PLLA/PCL, PGA/TMC (Poly(glycolicacid-co-trimethylene carbonate)), PDS, PEPBO or other absorbablepolyurethane, polyester, polycarbonate, Polyorthoesters, Polyanhydrides,Polyesteramides, and/or Polyoxaesters, for example. In variousembodiments, a tissue thickness compensator can be comprised of PGA/PLA(Poly(glycolic acid-co-lactic acid)) and/or PDS/PLA(Poly(p-dioxanone-co-lactic acid)), for example. In various embodiments,a tissue thickness compensator can be comprised of an organic material,for example. In certain embodiments, a tissue thickness compensator canbe comprised of Carboxymethyl Cellulose, Sodium Alginate, Cross-linkedHyaluronic Acid, and/or Oxidized regenerated cellulose, for example. Invarious embodiments, a tissue thickness compensator can comprise adurometer in the 3-7 Shore A (30-50 Shore 00) ranges with a maximumstiffness of 15 Shore A (65 Shore OO), for example. In certainembodiments, a tissue thickness compensator can undergo 40% compressionunder 3 lbf load, 60% compression under 6 lbf load, and/or 80%compression under 20 lbf load, for example. In certain embodiments, oneor more gasses, such as air, nitrogen, carbon dioxide, and/or oxygen,for example, can be bubbled through and/or contained within the tissuethickness compensator. In at least one embodiment, a tissue thicknesscompensator can comprise beads therein which comprise betweenapproximately 50% and approximately 75% of the material stiffnesscomprising the tissue thickness compensator.

In various embodiments, a tissue thickness compensator can comprisehyaluronic acid, nutrients, fibrin, thrombin, platelet rich plasma,Sulfasalazine (Azulfidine®—5ASA+Sulfapyridine diazobond))—prodrug—colonic bacterial (Azoreductase), Mesalamine (5ASA withdifferent prodrug configurations for delayed release), Asacol®(5ASA+Eudragit-S coated—pH>7 (coating dissolution)), Pentasa®(5ASA+ethylcellulose coated—time/pH dependent slow release), Mesasal®(5ASA+Eudragit-L coated—pH>6), Olsalazine (5ASA+5ASA—colonic bacterial(Azoreductase)), Balsalazide (5ASA+4Aminobenzoyl-B-alanine)—colonicbacterial (Azoreductase)), Granulated mesalamine, Lialda (delay and SRformulation of mesalamine), HMPL-004 (herbal mixture that may inhibitTNF-alpha, interleukin-1 beta, and nuclear-kappa B activation), CCX282-B(oral chemokine receptor antagonist that interferes with trafficking ofT lymphocytes into the intestinal mucosa), Rifaximin (nonabsorbablebroad-spectrum antibiotic), Infliximab, murine chymieric (monoclonalantibody directed against TNF-alpha-approved for reducing signs/symptomsand maintaining clinical remission in adult/pediatric patients withmoderate/severe luminal and fistulizing Crohn's disease who have hadinadequate response to conventional therapy), Adalimumab, Total HumanIgG1 (anti-TNF-alpha monoclonal antibody—approved for reducingsigns/symptoms of Crohn's disease, and for the induction and maintenanceof clinical remission in adult patients with moderate/severe activeCrohn's disease with inadequate response to conventional therapies, orwho become intolerant to Infliximab), Certolizumab pegoll, humanizedanti-TNF FAB′ (monoclonal antibody fragment linked to polyethyleneglycol—approved for reducing signs/symptoms of Crohn's disease and forthe induction and maintenance of response in adult patients w/moderate/severe disease with inadequate response to conventionaltherapies), Natalizumab, First non-TNF-alpha inhibitor (biologiccompound approved for Crohn's disease), Humanized monoclonal IgG4antibody (directed against alpha-4 integrin—FDA approved for inducingand maintaining clinical response and remission in patients withmoderate/severe disease with evidence of inflammation and who have hadinadequate response to or are unable to tolerate conventional Crohn'stherapies and inhibitors of TNF-alpha), concomitant Immunomodulatorspotentially given with Infliximab, Azathioprine 6-Mercaptopurine (purinesynthesis inhibitor—prodrug), Methotrexate (binds dihydrofolatereductase (DHFR) enzyme that participates in tetrahydrofolate synthesis,inhibits all purine synthesis), Allopurinol and Thioprine therapy, PPI,H2 for acid suppression to protect the healing line, C-Diff—Flagyl,Vancomycin (fecal translocation treatment; probiotics; repopulation ofnormal endoluminal flora), and/or Rifaximin (treatment of bacterialovergrowth (notably hepatic encephalopathy); not absorbed in GI tractwith action on intraluminal bacteria), for example.

As described herein, a tissue thickness compensator can compensate forvariations in the thickness of tissue that is captured within thestaples ejected from a staple cartridge and/or contained within a stapleline, for example. Stated another way, certain staples within a stapleline can capture thick portions of the tissue while other staples withinthe staple line can capture thin portions of the tissue. In suchcircumstances, the tissue thickness compensator can assume differentheights or thicknesses within the staples and apply a compressive forceto the tissue captured within the staples regardless of whether thecaptured tissue is thick or thin. In various embodiments, a tissuethickness compensator can compensate for variations in the hardness ofthe tissue. For instance, certain staples within a staple line cancapture highly compressible portions of the tissue while other stapleswithin the staple line can capture portions of the tissue which are lesscompressible. In such circumstances, the tissue thickness compensatorcan be configured to assume a smaller height within the staples thathave captured tissue having a lower compressibility, or higher hardness,and, correspondingly, a larger height within the staples that havecaptured tissue having a higher compressibility, or lower hardness, forexample. In any event, a tissue thickness compensator, regardless ofwhether it compensates for variations in tissue thickness and/orvariations in tissue hardness, for example, can be referred to as a‘tissue compensator’ and/or as a ‘compensator’, for example.

The devices disclosed herein can be designed to be disposed of after asingle use, or they can be designed to be used multiple times. In eithercase, however, the device can be reconditioned for reuse after at leastone use. Reconditioning can include any combination of the steps ofdisassembly of the device, followed by cleaning or replacement ofparticular pieces, and subsequent reassembly. In particular, the devicecan be disassembled, and any number of the particular pieces or parts ofthe device can be selectively replaced or removed in any combination.Upon cleaning and/or replacement of particular parts, the device can bereassembled for subsequent use either at a reconditioning facility, orby a surgical team immediately prior to a surgical procedure. Thoseskilled in the art will appreciate that reconditioning of a device canutilize a variety of techniques for disassembly, cleaning/replacement,and reassembly. Use of such techniques, and the resulting reconditioneddevice, are all within the scope of the present application.

Preferably, the invention described herein will be processed beforesurgery. First, a new or used instrument is obtained and if necessarycleaned. The instrument can then be sterilized. In one sterilizationtechnique, the instrument is placed in a closed and sealed container,such as a plastic or TYVEK bag. The container and instrument are thenplaced in a field of radiation that can penetrate the container, such asgamma radiation, x-rays, or high-energy electrons. The radiation killsbacteria on the instrument and in the container. The sterilizedinstrument can then be stored in the sterile container. The sealedcontainer keeps the instrument sterile until it is opened in the medicalfacility.

Any patent, publication, or other disclosure material, in whole or inpart, that is said to be incorporated by reference herein isincorporated herein only to the extent that the incorporated materialsdoes not conflict with existing definitions, statements, or otherdisclosure material set forth in this disclosure. As such, and to theextent necessary, the disclosure as explicitly set forth hereinsupersedes any conflicting material incorporated herein by reference.Any material, or portion thereof, that is said to be incorporated byreference herein, but which conflicts with existing definitions,statements, or other disclosure material set forth herein will only beincorporated to the extent that no conflict arises between thatincorporated material and the existing disclosure material.

While this invention has been described as having exemplary designs, thepresent invention may be further modified within the spirit and scope ofthe disclosure. This application is therefore intended to cover anyvariations, uses, or adaptations of the invention using its generalprinciples. Further, this application is intended to cover suchdepartures from the present disclosure as come within known or customarypractice in the art to which this invention pertains.

1. A surgical end effector, comprising: a staple cartridge comprising astaple; an anvil moveable relative to said staple cartridge, whereinsaid anvil comprises a staple forming surface; and a layer of materialcomprising: a proximal end portion, wherein said proximal end portion isreleasably secured to said staple cartridge; and a distal end portion,wherein said distal end portion is releasably secured to said anvil. 2.The surgical end effector of claim 1, wherein said layer of materialcomprises a tissue thickness compensator.
 3. The surgical end effectorof claim 1, wherein said staple cartridge further comprises a firsttissue contacting surface, and wherein said layer of material furthercomprises a second tissue contacting surface.
 4. The surgical endeffector of claim 1, wherein said staple cartridge further comprises aproximal end and a slot extending from said proximal end, and whereinsaid proximal end portion of said layer of material is releasablyreceived in said slot.
 5. The surgical end effector of claim 4, furthercomprising a firing element configured to move along at least a portionof said slot, wherein said firing element is configured to deform saidproximal end portion.
 6. The surgical end effector of claim 1, whereinsaid anvil further comprises a distal end and a slot extending from saiddistal end, and wherein said distal end portion of said layer ofmaterial is releasably received in said slot.
 7. The surgical endeffector of claim 1, wherein said proximal end portion further comprisesa first deformable clip, and wherein said distal end portion furthercomprises a second deformable clip.
 8. A surgical end effector,comprising: a staple cartridge comprising a plurality of staples and acartridge slot defined at least partially through said staple cartridge;an anvil comprising an anvil slot defined at least partially throughsaid anvil; and a layer of material comprising: a first attachmentportion, wherein said cartridge slot is configured to receive said firstattachment portion; and a second attachment portion, wherein said anvilslot is configured to receive said second attachment portion.
 9. Thesurgical end effector of claim 8, wherein said layer of material isremovably attached to said staple cartridge and said anvil.
 10. Thesurgical end effector of claim 9, further comprising a firing memberconfigured to translate along said cartridge slot, wherein said firingmember is configured to deflect said first attachment portion.
 11. Thesurgical end effector of claim 8, wherein said first attachment portionextends from a proximal end of said layer of material, and wherein saidsecond attachment portion extends from a distal end of said layer ofmaterial.
 12. The surgical end effector of claim 8, wherein said staplecartridge further comprises a first tissue contacting surface, andwherein said layer of material further comprises a second tissuecontacting surface.
 13. The surgical end effector of claim 8, whereinthe first attachment portion comprises a deflectable hook.
 14. Thesurgical end effector of claim 8, wherein said layer of materialcomprises a tissue thickness compensator.
 15. A surgical end effector,comprising: holding means for holding fasteners; clamping means forclamping tissue between said clamping means and said holding means; anda layer of material, comprising: a proximal means for releasablyattaching said layer of material to said holding means; and a distalmeans for releasably attaching said layer of material to said clampingmeans.
 16. The surgical end effector of claim 15, wherein said layer ofmaterial comprises tissue compensation means for compensating.
 17. Thesurgical end effector of claim 15, further comprising releasing meansfor releasing said layer of material from at least one of said holdingmeans or said clamping means.
 18. The surgical end effector of claim 15,wherein said proximal means comprises a deflectable clip.
 19. Thesurgical end effector of claim 18, wherein said holding means furthercomprises a plurality of fasteners and a slot configured to receive saiddeflectable clip. 20-24. (canceled)